JPWO2010050184A1 - Imaging unit - Google Patents

Abstract

The present invention relates to an imaging unit including an imaging device that performs photoelectric conversion. In order to improve convenience in various processes using an imaging device, an imaging unit capable of ensuring the strength of the imaging device while allowing light to pass through the imaging device is provided. The imaging unit (1) includes a substrate (11a) and a light receiving unit (11b) provided on the substrate (11a), converts light received by the light receiving unit (11b) into an electrical signal by photoelectric conversion, An image sensor (10) configured to transmit light and a glass substrate (19) bonded to the image sensor (10) and transmitting light are provided.

Description

  The present invention relates to an imaging unit including an imaging device that performs photoelectric conversion.

  2. Description of the Related Art In recent years, digital cameras that convert an object image into an electrical signal using an imaging device such as a charge coupled device (CCD) image sensor or a complementary metal-oxide semiconductor (CMOS) image sensor and digitize and record the electrical signal have been developed. It is popular.

  A digital single-lens reflex camera has a phase difference detection unit that detects a phase difference of a subject image, and thus has a phase difference detection AF function that performs autofocus (hereinafter also simply referred to as AF). According to the phase difference detection AF function, the defocus direction and the defocus amount can be detected, so that the moving time of the focus lens can be shortened and the focus can be quickly achieved (for example, Patent Document 1). In a conventional digital single lens reflex camera, in order to guide light from a subject to a phase difference detection unit, a movable mirror configured to be able to advance / retreat on an optical path from a lens barrel to an image sensor is provided.

  A so-called compact digital camera adopts an autofocus function by video AF using an image sensor (for example, Patent Document 2). In this way, the compact digital camera is miniaturized by eliminating the mirror for guiding the light from the subject to the phase difference detection unit. In such a compact digital camera, autofocus can be performed while exposing the image sensor. That is, while performing autofocus, various processes using the image sensor, for example, obtaining an image signal from a subject image formed on the image sensor and displaying it on the image display unit provided on the back of the camera, It can be recorded in the recording unit. This autofocus function by video AF is generally advantageous in that it has higher accuracy than phase difference detection AF.

JP 2007-163545 A JP 2007-135140 A

  However, the video AF cannot detect the defocus direction instantaneously like the digital camera according to Patent Document 2. For example, according to the contrast detection method AF, the focus is detected by detecting the contrast peak, but if the focus lens is not moved back and forth from the current position, the direction of the contrast peak, that is, the defocus direction is detected. Can not do it. Therefore, it takes time for focus detection.

  That is, the phase difference detection method AF is more advantageous from the viewpoint of reducing the time required for focus detection. However, in an imaging apparatus that employs phase difference detection AF such as a digital single-lens reflex camera according to Patent Document 1, in order to guide light from a subject to a phase difference detection unit, the lens barrel is moved to the imaging device. It is necessary to move a movable mirror on the optical path. Therefore, various processes using the image sensor cannot be performed while performing the phase difference detection method AF. Further, when the path of incident light is switched between the path toward the phase difference detection unit and the path toward the image sensor, it is necessary to move the movable mirror, and a time lag and noise for the movement of the movable mirror are generated.

  That is, the conventional imaging apparatus that performs the phase difference detection method AF is not convenient due to various processes using the imaging element.

  The present invention has been made in view of such a point, and the object of the present invention is to provide convenience in performing various processes using an image sensor and phase difference detection using a phase difference detection unit. It is to improve.

  As a result of intensive studies, the applicant of the present application has found that light transmitted through the image sensor is used in order to solve the above problems. That is, by performing focus detection by the phase difference detection method using light transmitted through the image sensor, the movable mirror can be eliminated, and processing by the image sensor and phase difference detection can be performed in parallel. Furthermore, by allowing light to pass through the image sensor, not only the phase difference detection but also convenience in performing various processes can be improved.

  However, in order to allow light to pass through the image sensor, it is necessary to form the image sensor thin, and this reduces the strength of the image sensor. That is, an object of the present invention is to provide an imaging unit capable of ensuring the strength of the image sensor while allowing the image sensor to transmit light.

  Therefore, the present invention reinforces the image sensor by bonding an optically transparent substrate to the substrate of the image sensor. Specifically, an imaging unit according to the present invention has a semiconductor substrate and a light receiving portion provided on the semiconductor substrate, converts light received by the light receiving portion into an electrical signal by photoelectric conversion, An imaging element configured to transmit light and an optically transparent substrate that is bonded to the imaging element and transmits light are provided.

  According to the present invention, even if an image pickup device is formed thin enough to transmit light by bonding an optical transmission substrate to the image pickup device, the image pickup device can be reinforced. By configuring the reinforcing substrate with an optically transparent substrate, the optically transparent substrate can also transmit light. Therefore, when light enters or exits the image sensor, the optical substrate It is possible to prevent the transparent substrate from interfering with the incidence or emission of the light.

FIG. 1 is a cross-sectional view of the image sensor according to the first embodiment. FIG. 2 is a block diagram of the camera. FIG. 3 is a cross-sectional view of the imaging unit. FIG. 4 is a plan view of the image sensor. FIG. 5 is a partially enlarged cross-sectional view showing a joint portion between the image sensor and the package. FIG. 6 is a plan view of the phase detection unit. FIG. 7 is a perspective view of the imaging unit. FIG. 8 is a flowchart showing the photographing operation until the release button is fully pressed. FIG. 9 is a flowchart showing the photographing operation after the release button is fully pressed. FIG. 10 is a cross-sectional view of an imaging unit according to the first modification. FIG. 11 is a cross-sectional view of an image sensor according to the second modification. FIG. 12 is a cross-sectional view of an image sensor according to the third modification. FIG. 13 is a cross-sectional view illustrating the bonding between the image sensor and the package according to the third modification. FIG. 14 is a cross-sectional view of the image sensor according to the second embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

Embodiment 1 of the Invention
A camera including the imaging unit 1 according to Embodiment 1 of the present invention will be described.

  As shown in FIG. 2, the camera 100 according to the first embodiment is an interchangeable-lens single-lens reflex digital camera. The camera 100 mainly has a main function of the camera system, and is removable from the camera body 4. The interchangeable lens 7 is mounted. The interchangeable lens 7 is attached to a body mount 41 provided on the front surface of the camera body 4. The body mount 41 is provided with an electrical section 41a.

-Camera body configuration-
The camera body 4 has an imaging unit 1 that acquires a subject image as a captured image, a shutter unit 42 that adjusts the exposure state of the imaging unit 1, and infrared light removal and moire phenomenon of the subject image incident on the imaging unit 1. And an image display unit 44 that includes an IR cut and OLPF (Optical Low Pass Filter) 43, a liquid crystal monitor, and displays captured images, live view images, and various types of information, and a body control unit 5. . This camera body 4 constitutes the imaging apparatus body.

  The camera body 4 is provided with a power switch 40a that operates to turn on / off the power of the camera system, and a release button 40b that is operated by the photographer during focusing and release.

  When the power is turned on by the power switch 40 a, power is supplied to each part of the camera body 4 and the interchangeable lens 7.

  The release button 40b is a two-stage type, and performs autofocus and AE, which will be described later, when pressed halfway, and releases when pressed fully.

  As will be described in detail later, the imaging unit 1 converts the subject image into an electrical signal by photoelectric conversion. The imaging unit 1 is configured to be movable in a plane perpendicular to the optical axis X by the blur correction unit 45.

  The body control unit 5 controls the operation of the body microcomputer 50, the nonvolatile memory 50 a, the shutter control unit 51 that controls the driving of the shutter unit 42, and the imaging unit 1, and converts the electrical signal from the imaging unit 1 to A / The imaging unit control unit 52 that performs D conversion and outputs the image data to the body microcomputer 50, and the reading of the image data from the image storage unit 58, which is a card-type recording medium or an internal memory, for example, and the recording of the image data in the image storage unit 58 The image reading / recording unit 53 to perform, the image recording control unit 54 for controlling the image reading / recording unit 53, the image display control unit 55 for controlling the display of the image display unit 44, and the image blur caused by the camera body 4 blur A blur detection unit 56 that detects the amount and a correction unit control unit 57 that controls the blur correction unit 45 are included. This body control part 5 comprises a control part.

  The body microcomputer 50 is a control device that controls the center of the camera body 4 and controls various sequences. For example, a CPU, a ROM, and a RAM are mounted on the body microcomputer 50. And the body microcomputer 50 can implement | achieve various functions because the program stored in ROM is read by CPU.

  The body microcomputer 50 receives input signals from the power switch 40a and the release button 40b, as well as a shutter control unit 51, an imaging unit control unit 52, an image readout / recording unit 53, an image recording control unit 54, and a correction unit control. The controller 57 is configured to output control signals to the shutter 57, the imaging unit controller 52, the image reading / recording unit 53, the image recording controller 54, the correction unit controller 57, and the like. Make control run. The body microcomputer 50 performs inter-microcomputer communication with a lens microcomputer 80 described later.

  For example, in accordance with an instruction from the body microcomputer 50, the imaging unit control unit 52 performs A / D conversion on the electrical signal from the imaging unit 1 and outputs it to the body microcomputer 50. The body microcomputer 50 performs predetermined image processing on the captured electric signal to create an image signal. The body microcomputer 50 transmits an image signal to the image reading / recording unit 53 and instructs the image recording control unit 54 to record and display an image, and stores the image signal in the image storage unit 58 and the image. The image signal is transmitted to the display control unit 55. The image display control unit 55 controls the image display unit 44 based on the transmitted image signal, and causes the image display unit 44 to display an image.

  Various information (main body information) related to the camera body 4 is stored in the nonvolatile memory 50a. The body information includes, for example, the model name for identifying the camera body 4 such as the manufacturer name, date of manufacture, model number, software version installed in the body microcomputer 50, and information on the firmware upgrade. Information (main body specifying information), information about whether the camera body 4 is equipped with means for correcting image blur such as the blur correction unit 45 and the blur detection unit 56, the model number and sensitivity of the blur detection unit 56, etc. It also includes information on detection performance, error history, etc. These pieces of information may be stored in the memory unit in the body microcomputer 50 instead of the nonvolatile memory 50a.

  The shake detection unit 56 includes an angular velocity sensor that detects the movement of the camera body 4 caused by camera shake or the like. The angular velocity sensor outputs a positive / negative angular velocity signal according to the direction in which the camera body 4 moves with reference to the output when the camera body 4 is stationary. In the present embodiment, two angular velocity sensors are provided to detect the two directions of the yawing direction and the pitching direction. The output angular velocity signal is subjected to filter processing, amplifier processing, and the like, converted into a digital signal by an A / D conversion unit, and provided to the body microcomputer 50.

-Composition of interchangeable lens-
The interchangeable lens 7 constitutes an imaging optical system for connecting a subject image to the imaging unit 1 in the camera body 4, and mainly includes a focus adjustment unit 7A that performs focusing and an aperture adjustment unit 7B that adjusts the aperture. The image blur correction unit 7C for correcting the image blur by adjusting the optical path and the lens control unit 8 for controlling the operation of the interchangeable lens 7 are provided.

  The interchangeable lens 7 is attached to the body mount 41 of the camera body 4 via the lens mount 71. In addition, the lens mount 71 is provided with an electrical piece 71 a that is electrically connected to the electrical piece 41 a of the body mount 41 when the interchangeable lens 7 is attached to the camera body 4.

  The focus adjustment unit 7A includes a focus lens group 72 that adjusts the focus. The focus lens group 72 is movable in the direction of the optical axis X in a section from the closest focus position to the infinite focus position defined as the standard of the interchangeable lens 7. In addition, the focus lens group 72 needs to be movable back and forth in the optical axis X direction with respect to the focus position in the case of focus position detection by a contrast detection method to be described later. It has a lens shift margin section that can move further back and forth in the optical axis X direction than the section to the infinite focus position. The focus lens group 72 does not necessarily need to be composed of a plurality of lenses, and may be composed of a single lens.

  The diaphragm adjustment unit 7B is configured by a diaphragm unit 73 that adjusts the diaphragm or opening. The diaphragm 73 constitutes a light quantity adjustment unit.

  The lens image blur correction unit 7C includes a blur correction lens 74 and a blur correction lens driving unit 74a that moves the blur correction lens 74 in a plane perpendicular to the optical axis X.

  The lens controller 8 receives a control signal from the lens microcomputer 80, the nonvolatile memory 80 a, the focus lens group controller 81 that controls the operation of the focus lens group 72, and the focus lens group controller 81, and receives the focus lens group 72. A focus drive unit 82 for driving the lens, a diaphragm control unit 83 for controlling the operation of the diaphragm unit 73, a blur detection unit 84 for detecting blur of the interchangeable lens 7, and a blur correction lens unit for controlling the blur correction lens driving unit 74a. And a control unit 85.

  The lens microcomputer 80 is a control device that controls the center of the interchangeable lens 7, and is connected to each unit mounted on the interchangeable lens 7. Specifically, the lens microcomputer 80 is equipped with a CPU, a ROM, and a RAM, and various functions can be realized by reading a program stored in the ROM into the CPU. For example, the lens microcomputer 80 has a function of setting a lens image blur correction device (such as the blur correction lens driving unit 74a) to a correctable state or an uncorrectable state based on a signal from the body microcomputer 50. Further, the body microcomputer 50 and the lens microcomputer 80 are electrically connected by contact between the electrical slice 71a provided on the lens mount 71 and the electrical slice 41a provided on the body mount 41, so that information can be transmitted and received between them. It has become.

  In addition, various information (lens information) related to the interchangeable lens 7 is stored in the nonvolatile memory 80a. The lens information includes, for example, a model for specifying the interchangeable lens 7 such as a manufacturer name, a date of manufacture, a model number, a software version installed in the lens microcomputer 80, and information on firmware upgrade of the interchangeable lens 7. Information (lens specifying information), information on whether or not the interchangeable lens 7 is equipped with means for correcting image blur such as the blur correction lens driving unit 74a and blur detection unit 84, and means for correcting image blur , Information on the detection performance such as the model number and sensitivity of the blur detection unit 84, information on the correction performance such as the model number of the blur correction lens driving unit 74a and the maximum correctable angle (lens side correction performance information), Software version for image blur correction is included. Further, the lens information includes information on power consumption necessary for driving the blur correction lens driving unit 74a (lens side power consumption information) and information on driving method of the blur correction lens driving unit 74a (lens side driving method information). It is. The nonvolatile memory 80a can store information transmitted from the body microcomputer 50. These pieces of information may be stored in a memory unit in the lens microcomputer 80 instead of the nonvolatile memory 80a.

  The focus lens group control unit 81 includes an absolute position detection unit 81a that detects an absolute position of the focus lens group 72 in the optical axis direction, and a relative position detection unit 81b that detects a relative position of the focus lens group 72 in the optical axis direction. Have. The absolute position detector 81 a detects the absolute position of the focus lens group 72 in the casing of the interchangeable lens 7. The absolute position detector 81a is constituted by, for example, a contact encoder board of several bits and a brush, and is configured to be able to detect the absolute position. The relative position detector 81b alone cannot detect the absolute position of the focus lens group 72, but can detect the moving direction of the focus lens group 72, and uses, for example, a two-phase encoder. Two two-phase encoders, such as a rotary pulse encoder, an MR element, and a Hall element, are provided that alternately output binary signals at an equal pitch according to the position of the focus lens group 72 in the optical axis direction. These pitches are installed so as to shift the phases. The lens microcomputer 80 calculates the relative position of the focus lens group 72 in the optical axis direction from the output of the relative position detector 81b.

  The shake detection unit 84 includes an angular velocity sensor that detects the movement of the interchangeable lens 7 caused by camera shake or the like. The angular velocity sensor outputs positive and negative angular velocity signals according to the direction in which the interchangeable lens 7 moves with reference to the output when the interchangeable lens 7 is stationary. In the present embodiment, two angular velocity sensors are provided to detect the two directions of the yawing direction and the pitching direction. The output angular velocity signal is subjected to filter processing, amplifier processing, and the like, converted into a digital signal by an A / D conversion unit, and provided to the lens microcomputer 80.

  The blur correction lens unit control unit 85 includes a movement amount detection unit (not shown). The movement amount detection unit is a detection unit that detects an actual movement amount of the blur correction lens 74. The blur correction lens unit control unit 85 performs feedback control of the blur correction lens 74 based on the output from the movement amount detection unit.

  Although an example in which the camera shake detection units 56 and 84 and the camera shake correction devices 45 and 74a are mounted on both the camera body 4 and the interchangeable lens 7 has been shown, A correction device may be mounted, and neither of the shake detection unit and the shake correction device may be mounted (in this case, the above-described sequence related to the shake correction may be excluded).

-Image unit configuration-
As shown in FIG. 3, the imaging unit 1 includes an imaging element 10 for converting a subject image into an electrical signal, a glass substrate 19 bonded to the imaging element 10, and a package 31 for holding the imaging element 10. And a phase difference detection unit 20 for performing focus detection by the phase difference detection method.

  The imaging device 10 is a back-illuminated interline CCD image sensor, and as shown in FIG. 1, a photoelectric conversion unit 11 made of a semiconductor material, a vertical register 12, a transfer path 13, and a mask 14 And a color filter 15.

  The photoelectric conversion unit 11 includes a substrate 11a and a plurality of light receiving units (also referred to as pixels) 11b, 11b,... Arranged on the substrate 11a.

The substrate 11a is a semiconductor substrate composed of Si (silicon) base. Specifically, the substrate 11a is formed of a Si single crystal substrate or an SOI (Silicon On Insulator wafer). In particular, the SOI substrate has a sandwich structure of an Si thin film and an SiO ₂ thin film, and can stop the reaction in the SiO ₂ layer in an etching process or the like, which is advantageous for stable substrate processing.

  The light receiving portion 11b is composed of a photodiode and absorbs light to generate charges. The light receiving portions 11b, 11b,... Are respectively provided in minute square pixel regions arranged in a matrix on the surface of the substrate 11a (the lower surface in FIG. 1) (see FIG. 4).

  As described above, the imaging element 10 is a back-illuminated type, and the light from the subject is on the opposite side of the surface (hereinafter also referred to as the front surface) on the substrate 11a where the light receiving portions 11b, 11b,. Incident from the surface (hereinafter also referred to as the back surface).

  The vertical register 12 is provided for each light receiving portion 11b on the front surface side of the substrate 11a, and has a role of temporarily storing charges accumulated in the light receiving portion 11b. That is, the electric charge accumulated in the light receiving unit 11 b is transferred to the vertical register 12. The charges transferred to the vertical register 12 are transferred to a horizontal register (not shown) via the transfer path 13 and sent to an amplifier (not shown). The electric charge sent to the amplifier is amplified and taken out as an electric signal.

  The mask 14 includes an incident-side mask 14a provided on the surface of the substrate 11a, and an emission-side mask 14b provided so as to cover the light receiving unit 11b, the vertical register 12, and the transfer path 13 from the side opposite to the substrate 11a. is doing. The incident side mask 14a is provided between the light receiving portions 11b and 11b on the surface of the substrate 11a. The vertical register 12 and the transfer path 13 are provided so as to overlap the incident side mask 14a. In this way, the incident side mask 14 a prevents the light transmitted through the substrate 11 a from entering the vertical register 12 and the transfer path 13. The emission side mask 14b reflects the light transmitted through the light receiving parts 11b, 11b,... Without being absorbed by the light receiving parts 11b, 11b,. In addition, a plurality of through holes 14c (FIG. 1) for emitting light that has passed through the light receiving portion 11b to the back side of the image sensor 10 (in the present embodiment, the side opposite to the glass substrate 19) is provided in the emission side mask 14b. , Only one is shown). Note that the emission side mask 14b may not be provided.

  A protective layer 18 made of an optically transparent resin is provided on the surface of the substrate 11a so as to cover the light receiving portion 11b, the vertical register 12, the transfer path 13, and the mask 14.

  The color filter 15 is provided for each of the small square pixel regions corresponding to each light receiving portion 11b on the back side of the substrate 11a. The color filter 15 is for transmitting only a specific color, and is a thin film interference filter formed of a dielectric. In this embodiment, as shown in FIG. 4, a so-called Bayer type primary color filter is used. That is, for the entire image sensor 10, when four color filters 15, 15,... (Or four pixel regions) adjacent to 2 rows and 2 columns are defined as one repeating unit, Two green color filters (that is, color filters having higher transmittance than the visible light wavelength region of colors other than green with respect to the green visible light wavelength region) 15g are arranged in the diagonal direction, A diagonally red color filter (that is, a color filter having a higher transmittance than the visible light wavelength range of colors other than red with respect to the red visible light wavelength range) 15r and a blue color filter (that is, And a color filter 15b having a higher transmittance than the visible light wavelength region of colors other than blue with respect to the blue visible light wavelength region. As a whole, every other green color filter 15g, 15g,... Is arranged vertically and horizontally. The color filter 15 may be a complementary color filter that transmits each color of CyMYG. The color filter 15 is vapor-deposited on the bonding surface of the glass substrate 19 with the image sensor 10.

  The glass substrate 19 is composed of a borosilicate glass substrate. This glass substrate 19 corresponds to an optically transparent substrate. The glass substrate 19 is anodically bonded to the substrate 11a. Here, since borosilicate glass is rich in mobile ions, anodic bonding with the substrate 11a is possible by configuring the glass substrate 19 with borosilicate glass. Further, as described above, the color filter 15 is deposited on the surface of the glass substrate 19 to be bonded to the substrate 11a. Since the color filter 15 is a dielectric, the glass substrate 19 is attached to the substrate 11a as an anode. Can be joined.

  As a material of the glass substrate 19, for example, Pyrex (registered trademark) manufactured by Corning, or Tempax Duran manufactured by Schott can be employed. Further, the bonding between the glass substrate 19 and the substrate 11a is not limited to the anodic bonding, and may be bonding via an adhesive or the like.

Here, the substrate 11a to be anodically bonded to the glass substrate 19 may be anodically bonded to the glass substrate 19 after being polished to a desired thickness (for example, 1 to 5 μm) or thicker than the desired thickness. After the substrate 11a is anodically bonded, it may be polished to a desired thickness by etching or the like. When the substrate 11a thicker than the desired thickness is used, the substrate 11a that has been anodically bonded is heat-treated to form a SiO ₂ layer on the surface of the substrate 11a opposite to the glass substrate 19. Then, a thin (eg, 1 to 2 μm) Si layer is formed by dissolving only the SiO ₂ layer with hydrofluoric acid. At the same time, the light receiving portion 11b, the vertical register 12, the transfer path 13 and the like are formed in the Si layer by a semiconductor process.

  In the imaging device 10 configured as described above, light enters from the glass substrate 19 side. Specifically, light that has passed through the glass substrate 19 is incident on the color filters 15r, 15g, and 15b, and only light of a color corresponding to each color filter 15 is transmitted through the color filter 15 and incident on the back surface of the substrate 11a. To do. Since the substrate 11a is very thin (that is, the substrate 11a is formed to have a thickness that allows light to pass through), the light incident on the substrate 11a passes through the substrate 11a and reaches the surface of the substrate 11a. It reaches the arranged light receiving portions 11b, 11b,. Here, since the incident side mask 14a is provided in the region where the light receiving portions 11b, 11b,... Are not provided on the surface of the substrate 11a, no light enters the vertical register 12 or the transfer path 13. . In addition, the light receiving portions 11b, 11b,... Have a very high quantum efficiency because the entire surface is open to the light incident side (substrate 11a side) unlike the image sensor 410 of the second embodiment described later. Become. Each light receiving portion 11b absorbs light and generates electric charges. Here, since the emission side mask 14b is provided on the opposite side of the light receiving portion 11b from the substrate 11a, the light transmitted through the light receiving portion 11b without being absorbed by the light receiving portion 11b is transmitted to the emission side mask. The light is reflected by 14b and enters the light receiving unit 11b again. By doing so, the quantum efficiency can be further increased. The electric charge generated in each light receiving unit 11b is sent to the amplifier via the vertical register 12 and the transfer path 13 and is output as an electric signal. At this time, since light of a specific color transmitted through the color filters 15r, 15g, and 15b is incident on the light receiving portions 11b, 11b,..., The colors corresponding to the color filters 15 are received from the light receiving portions 11b. The received light quantity is obtained as an output.

  Thus, the image sensor 10 converts the subject image formed on the imaging surface into an electrical signal by performing photoelectric conversion at the light receiving portions 11b, 11b,... On the entire imaging surface.

  The imaging device 10 configured in this way is held in a package 31 (see FIG. 3). The package 31 constitutes a holding unit.

  Specifically, the package 31 is provided with a circuit board 32 on a flat bottom plate 31a, and with standing walls 31b, 31b,. The image sensor 10 is mounted on the circuit board 32 so as to be covered on all sides by the standing walls 31b, 31b,.

  Specifically, as shown in FIG. 5, the light receiving unit 11 b, the vertical register 12, the transfer path 13, the mask 14, the protective layer 18, and the like are not provided at the peripheral edge of the substrate 11 a of the image sensor 10. 13 and the wiring for enabling electrical connection with the vertical register 12 and the like are exposed.

  On the other hand, the circuit board 32 has a board base 32a, and a circuit pattern 32b is provided on the surface (subject side surface) of the board base 32a at a position facing the wiring of the board 11a of the image sensor 10. . Then, the peripheral portion of the substrate 11a of the image sensor 10 is overlapped with the circuit board 32 from the subject side, and both are joined by thermal welding to electrically connect the wiring of the substrate 11a of the image sensor 10 and the circuit pattern 32b. is doing.

  Further, a cover glass 33 is attached to the tips of the standing walls 31b, 31b,... Of the package 31 so as to cover the imaging surface (back surface) of the imaging device 10. The cover glass 33 protects the image pickup surface of the image pickup device 10 from dust and the like.

  Here, the bottom plate 31a of the package 31 has the same number as the passage holes 14c, 14c,... In the position corresponding to the passage holes 14c, 14c,. ), The openings 31c, 31c,. Through the openings 31c, 31c,..., The light transmitted through the image sensor 10 reaches a phase difference detection unit 20 described later.

  Note that the opening 31 c is not necessarily formed through the bottom plate 31 a of the package 31. That is, as long as the light transmitted through the image sensor 10 reaches the phase difference detection unit 20, a configuration such as forming a transparent portion or a semi-transparent portion on the bottom plate 31a may be used.

  The phase difference detection unit 20 is provided on the back side (opposite to the subject) of the image sensor 10 and receives the transmitted light from the image sensor 10 to perform focus detection by the phase difference detection method. Specifically, the phase difference detection unit 20 converts the received transmitted light into an electric signal for distance measurement. This phase difference detection unit 20 constitutes a phase difference detection unit.

  3 and 6, the phase difference detection unit 20 includes a condenser lens unit 21, a mask member 22, a separator lens unit 23, a line sensor unit 24, the condenser lens unit 21, the mask member 22, And a module frame 25 to which the separator lens unit 23 and the line sensor unit 24 are attached. The condenser lens unit 21, the mask member 22, the separator lens unit 23, and the line sensor unit 24 are arranged in this order from the image sensor 10 side along the thickness direction of the image sensor 10.

  The condenser lens unit 21 is a unit in which a plurality of condenser lenses 21a, 21a,. As many condenser lenses 21a, 21a,... Are provided as there are passage holes 14c, 14c,. Each condenser lens 21 a is for condensing incident light, condenses the light that is transmitted through the image sensor 10 and is spreading, and guides it to a separator lens 23 a described later of the separator lens unit 23. Each condenser lens 21a has an incident surface 21b formed in a convex shape, and the vicinity of the incident surface 21b is formed in a cylindrical shape.

  By providing the condenser lens 21a, the incident angle to the separator lens 23a is increased (the incident angle is reduced), so that the aberration of the separator lens 23a can be suppressed and the object image interval on the line sensor 24a described later can be reduced. Can be small. As a result, the separator lens 23a and the line sensor 24a can be reduced in size. In addition, when the focus position of the subject image from the image pickup optical system is greatly deviated from the image pickup unit 1 (specifically, when it is greatly deviated from the image pickup device 10 of the image pickup unit 1), the contrast of the image is remarkably lowered. According to the embodiment, it is possible to suppress a decrease in contrast by the reduction effect of the condenser lens 21a and the separator lens 23a and to widen the focus detection range. Note that the condenser lens unit 21 may not be provided in the case of high-accuracy phase difference detection in the vicinity of the focal position, or when the dimensions of the separator lens 23a, the line sensor 24a, etc. are sufficient.

  The mask member 22 is disposed between the condenser lens unit 21 and the separator lens unit 23. In the mask member 22, two mask openings 22a and 22a are formed for each position corresponding to each separator lens 23a. That is, the mask member 22 divides the lens surface of the separator lens 23a into two regions, and only the two regions are exposed to the condenser lens 21a side. That is, the mask member 22 divides the light collected by the condenser lens 21a into two light fluxes and makes the light incident on the separator lens 23a. This mask member 22 can prevent harmful light from one separator lens 23a adjacent to the other separator lens 23a from entering. The mask member 22 need not be provided.

  The separator lens unit 23 includes a plurality of separator lenses 23a, 23a,..., And the separator lenses 23a, 23a,. The separator lenses 23a, 23a,... Are provided in the same number as the passage holes 14c, 14c,. Each separator lens 23a forms two light fluxes incident through the mask member 22 on the line sensor 24a as two identical subject images.

  The line sensor unit 24 includes a plurality of line sensors 24a, 24a,... And an installation portion 24b for installing the line sensors 24a, 24a,. The number of line sensors 24a, 24a,... Is the same as the number of passage holes 14c, 14c,. Each line sensor 24a receives an image formed on the imaging surface and converts it into an electrical signal. That is, the interval between two subject images can be detected from the output of the line sensor 24a, and the defocus amount (ie, defocus amount (Df amount)) of the subject image formed on the image sensor 10 based on the interval. It is possible to determine in which direction the focus is deviated (that is, the defocus direction) (hereinafter, the Df amount, the defocus direction, and the like are also referred to as defocus information).

  The condenser lens unit 21, the mask member 22, the separator lens unit 23, and the line sensor unit 24 configured as described above are disposed in the module frame 25.

  The module frame 25 is a member formed in a frame shape, and an attachment portion 25a that protrudes inward is provided on the inner periphery thereof. A first mounting portion 25b and a second mounting portion 25c are formed stepwise on the imaging element 10 side of the mounting portion 25a. Further, a third mounting portion 25d is formed on the side of the mounting portion 25a opposite to the image sensor 10.

  From the image sensor 10 side, the mask member 22 is attached to the second attachment portion 25c of the module frame 25, and the condenser lens unit 21 is attached to the first attachment portion 25b. The condenser lens unit 21 and the mask member 22 are formed so that the peripheral edge fits into the module frame 25 as shown in FIGS. 3 and 6 when attached to the first attachment portion 25b and the second attachment portion 25c, respectively. And thereby positioned with respect to the module frame 25.

  On the other hand, the separator lens unit 23 is attached to the third attachment portion 25 d of the module frame 25 from the opposite side of the image sensor 10. The third mounting portion 25d is provided with a positioning pin 25e and a direction reference pin 25f that protrude on the opposite side of the condenser lens unit 21. On the other hand, the separator lens unit 23 is formed with positioning holes 23b and direction reference holes 23c corresponding to the positioning pins 25e and the direction reference pins 25f, respectively. The diameters of the positioning pins 25e and the positioning holes 23b are set so as to be fitted. On the other hand, the diameters of the direction reference pin 25f and the direction reference hole 23c are set so as to fit gently. That is, the separator lens unit 23 inserts the positioning hole 23b and the direction reference hole 23c into the positioning pin 25e and the direction reference pin 25f of the third attachment part 25d, respectively, so that the direction when attaching to the third attachment part 25d, etc. The posture is defined, and the positioning is performed with respect to the third mounting portion 25d by fitting the positioning hole 23b and the positioning pin 25e. Thus, when the separator lens unit 23 is mounted with its orientation and position determined, the lens surfaces of the separator lenses 23a, 23a,... Face the condenser lens unit 21 and face the mask openings 22a, 22a. become.

  Thus, the condenser lens unit 21, the mask member 22, and the separator lens unit 23 are attached while being positioned with respect to the module frame 25. That is, the positional relationship between the condenser lens unit 21, the mask member 22, and the separator lens unit 23 is positioned via the module frame 25.

  The line sensor unit 24 is attached to the module frame 25 from the back side of the separator lens unit 23 (the side opposite to the condenser lens unit 21). At this time, the line sensor unit 24 is attached to the module frame 25 in a state where the light transmitted through each separator lens 23a is positioned so as to enter the line sensor 24a.

  Therefore, by attaching the condenser lens unit 21, the mask member 22, the separator lens unit 23, and the line sensor unit 24 to the module frame 25, light incident on the condenser lenses 21a, 21a,. Are transmitted through the mask member 22 and incident on the separator lenses 23a, 23a,..., And the light transmitted through the separator lenses 23a, 23a,... Forms an image on the line sensors 24a, 24a,. The lenses 21a, 21a,..., The mask member 22, the separator lenses 23a, 23a,... And the line sensors 24a, 24a,.

  The image sensor 10 and the phase difference detection unit 20 configured as described above are joined to each other. Specifically, the opening 31c of the package 31 in the image sensor 10 and the condenser lens 21a in the phase difference detection unit 20 are configured to fit each other. That is, the module frame 25 is bonded to the package 31 in a state where the condenser lenses 21a, 21a,... In the phase difference detection unit 20 are fitted into the openings 31c, 31c,. By doing so, the imaging device 10 and the phase difference detection unit 20 can be joined in a state of being positioned with respect to each other. In this way, the condenser lenses 21a, 21a,..., The separator lenses 23a, 23a,... And the line sensors 24a, 24a, etc. are integrated into a unit and attached to the package 31 in a united state.

  At this time, all the openings 31c, 31c,... And all the condenser lenses 21a, 21a,. Alternatively, only some of the openings 31c, 31c,... And the condenser lenses 21a, 21a,... Are fitted, and the remaining openings 31c, 31c,. You may comprise. In the latter case, the condenser lens 21a closest to the center of the imaging surface and the opening 31c are configured to be fitted to perform positioning within the imaging surface, and further, the condenser lens 21a and the aperture that are farthest from the center of the imaging surface. It is preferable that positioning is performed around the condenser lens 21a and the opening 31c (that is, the rotation angle) in the center of the imaging surface by being configured so as to be fitted with 31c.

  In this way, as a result of joining the image sensor 10 and the phase difference detection unit 20, a pair of mask openings of the condenser lens 21a and the mask member 22 are provided on the back side of the image sensor 10 for each of the passage holes 14c of the emission side mask 14b. 22a, 22a, separator lens 23a and line sensor 24a are arranged.

  In this way, by forming the openings 31c, 31c,... In the bottom plate 31a of the package 31 that accommodates the image sensor 10 with respect to the image sensor 10 configured to transmit light, the light transmitted through the image sensor 10 is formed. Can easily reach the back side of the package 31, and the phase difference detection unit 20 is disposed on the back side of the package 31 so that the light transmitted through the image sensor 10 is received by the phase difference detection unit 20. The configuration can be easily realized.

  In addition, the openings 31c, 31c,... Formed in the bottom plate 31a of the package 31 may adopt any configuration as long as the configuration allows the light transmitted through the image sensor 10 to pass through to the back side of the package 31. By forming the openings 31c, 31c,... Which are holes, the light transmitted through the image sensor 10 can reach the back side of the package 31 without being attenuated.

  Further, the phase difference detection unit 20 can be positioned with respect to the image sensor 10 by using the openings 31c, 31c,... By fitting the condenser lenses 21a, 21a,. . In the case where the condenser lenses 21a, 21a,... Are not provided, the phase difference detection unit for the image sensor 10 can be similarly formed by configuring the separator lenses 23a, 23a,. 20 positionings can be performed.

  At the same time, the bottom plate 31a of the package 31 can be passed through the condenser lenses 21a, 21a,... And close to the substrate 11a, so that the imaging unit 1 can be configured compactly.

  Further, three passage holes 14c are formed in the exit side mask 14b of the image sensor 10, and three sets of condenser lenses 21a, separator lenses 23a, and line sensors 24a are provided corresponding to the passage holes 14c, 14c, 14c. However, it is not limited to this. The number of these is not limited to three, and can be set to an arbitrary number. For example, as shown in FIG. 7, nine passing holes 14c, 14c,... May be formed, and nine sets of condenser lens 21a, separator lens 23a, and line sensor 24a may be provided.

  The operation of the imaging unit 1 configured as described above will be described below.

  When light from the subject enters the imaging unit 1, the light passes through the cover glass 33 and enters the glass substrate 19. The light passes through the glass substrate 19 and enters the back surface of the substrate 11 a of the image sensor 10. At this time, the light passes through the color filters 15r, 15g, and 15b, so that only light of a color corresponding to each color filter 15 enters the substrate 11a. The light incident on the substrate 11a passes through the substrate 11a and reaches the light receiving portions 11b, 11b,... On the surface of the substrate 11a. Since the incident side mask 14a is provided on the surface of the substrate 11a, light does not enter the vertical register 12 or the transfer path 13, and light enters only the light receiving portions 11b, 11b,. Each light receiving portion 11b absorbs light and generates electric charges. Here, not all of the light incident on the light receiving portion 11b is absorbed by the light receiving portion 11b, and a part of the light is transmitted through the light receiving portion 11b, but is emitted to a position where it has passed through the light receiving portion 11b. Since the side mask 14b is provided, the light transmitted through the light receiving portion 11b is reflected by the emission side mask 14b and enters the light receiving portion 11b again. The electric charge generated in the light receiving unit 11b is sent to the amplifier via the vertical register 12 and the transfer path 13, and is output as an electric signal. In this way, the image sensor 10 converts the subject image formed on the imaging surface into an electrical signal for creating an image signal by the light receiving units 11b converting the light into electrical signals on the entire imaging surface.

  However, the light transmitted through the light receiving portions 11b, 11b,... Of the image sensor 10 exits to the back side of the image sensor 10 through the passage holes 14c, 14c,. And the light which permeate | transmitted the image pick-up element 10 injects into the condenser lenses 21a, 21a, ... fitted to the openings 31c, 31c, ... of the package 31. The light condensed by passing through each condenser lens 21a is divided into two light beams when passing through each pair of mask openings 22a, 22a formed in the mask member 22, and enters each separator lens 23a. . The light thus divided into pupils passes through the separator lens 23a and forms an identical subject image at two positions on the line sensor 24a. The line sensor 24a creates and outputs an electrical signal from the subject image by photoelectric conversion.

  Next, processing in the body microcomputer 50 for the electrical signal converted by the image sensor 10 will be described.

  An electrical signal output from the image sensor 10 is input to the body microcomputer 50 via the image capturing unit controller 52. Then, the body microcomputer 50 obtains the subject image formed on the imaging surface by obtaining the position information of each light receiving unit 11b and the output data corresponding to the amount of light received by the light receiving unit 11b from the entire imaging surface of the image sensor 10. Get as an electrical signal.

  Here, even if the light receiving units 11b, 11b,... Receive the same amount of light, the accumulated charge amounts differ depending on the wavelength of the light, so that the outputs from the light receiving units 11b, 11b,. Correction is performed according to the type of the color filters 15r, 15g, and 15b provided. For example, an R pixel 11b provided with a red color filter 15r, a G pixel 11b provided with a green color filter 15g, and a B pixel 11b provided with a blue color filter 15b have colors corresponding to the respective color filters. When the same amount of light is received, the correction amount of each pixel is set so that the outputs from the R pixel 11b, the G pixel 11b, and the B pixel 11b are at the same level.

  In addition, in this embodiment, by providing the passage holes 14c, 14c,... Of the emission side mask 14b, the amount of received light in the portion corresponding to the passage holes 14c, 14c,. Less than As a result, the output data output from the pixels 11b, 11b,... Provided at the positions corresponding to the through holes 14c, 14c,. When image processing similar to that of data is performed, there is a possibility that images of portions corresponding to the passage holes 14c, 14c,... Are not properly captured (for example, they are captured darkly). Therefore, the output of each pixel 11b in the passage holes 14c, 14c,... Is corrected so as to eliminate the influence of the passage holes 14c, 14c,... (For example, the output of each pixel 11b in the passage holes 14c, 14c,. Etc.)

  Further, the reduction in output varies depending on the wavelength of light. Specifically, the longer the wavelength, the higher the transmittance of the substrate 11a, and the greater the decrease in output due to the passage hole 14c. Therefore, there is a difference in the decrease in output due to the passage hole 14c depending on the type of the color filters 15r, 15g, and 15b. Accordingly, the correction for eliminating the influence of the passage hole 14c on each pixel 11b corresponding to the passage hole 14c is made different in accordance with the wavelength of the light received by each pixel 11b. Specifically, for each pixel 11b corresponding to the passage hole 14c, the correction amount is increased as the wavelength of light received by each pixel 11b is longer.

  Here, in each pixel 11b, as described above, a correction amount for eliminating the difference in accumulated charge amount depending on the type of light received is set, and in addition to the correction for eliminating the difference in accumulated charge amount due to this color type. Thus, the correction for eliminating the influence of the passage hole 14c is made. That is, the correction amount for correcting the influence of the passage hole 14c is the correction amount for each pixel 11b corresponding to the passage hole 14c and the pixel 11b corresponding to a position other than the passage hole 14c and receiving the same color. This is the difference from the correction amount for the pixel 11b. In the present embodiment, the correction amount is varied for each color according to the relationship shown below. By doing so, a stable image output can be obtained.

Rk>Gk> Bk (1)
here,
Rk: R pixel correction amount of the passage hole 14c−R pixel correction amount other than the passage hole 14c Gk: G pixel correction amount of the passage hole 14c−G pixel correction amount other than the passage hole 14c Bk: B pixel correction amount of the passage hole 14c -It is set as B pixel correction amount other than the passage hole 14c.

  That is, among the three colors of red, green, and blue, red, which has a long wavelength, has the highest transmittance, so that the difference in correction amount at the red pixel is the largest. In addition, since blue, which has a short wavelength among the three colors, has the lowest transmittance, the difference in the correction amount between the blue pixels is the smallest.

  That is, the correction amount of the output of each pixel 11b of the image sensor 10 depends on whether or not each pixel 11b is located at a position corresponding to the passage hole 14c and the color type of the color filter 15 corresponding to each pixel 11b. To be determined. Each correction amount is set so that, for example, the white balance and / or luminance of the displayed image are equal by the output from the pixel 11b corresponding to the passage hole 14c and the output from the pixel 11b corresponding to a position other than the passage hole 14c. To be determined.

  The body microcomputer 50 corrects the output data from the light receiving portions 11b, 11b,... In this way, and then, based on the output data, the position information, color information, and luminance information in each light receiving portion, that is, the pixel 11b. Create an image signal containing. Thus, an image signal of the subject image formed on the imaging surface of the image sensor 10 is obtained.

  By correcting the output from the image sensor 10 in this way, the subject image can be appropriately captured even in the image sensor 10 provided with the passage holes 14c, 14c,.

  On the other hand, an electrical signal output from the line sensor unit 24 is also input to the body microcomputer 50. Based on the output from the line sensor unit 24, the body microcomputer 50 obtains the interval between the two subject images formed on the line sensor 24a, and uses the obtained interval to determine the subject image to be imaged on the image sensor 10. The focus state can be detected. For example, the two subject images formed on the line sensor 24a have a predetermined reference when the subject image formed on the image sensor 10 through the imaging lens is accurately formed (focused). Positioned at a predetermined reference position with a gap. On the other hand, when the subject image is formed in front of the image sensor 10 in the optical axis direction (front pin), the interval between the two subject images is narrower than the reference interval at the time of focusing. On the other hand, when the subject image is formed behind the image sensor 10 in the optical axis direction (rear pin), the interval between the two subject images is wider than the reference interval at the time of focusing. That is, after amplifying the output from the line sensor 24a, it is possible to know whether the in-focus state or the out-of-focus state, the front pin or the rear pin, or the amount of Df by calculating with the arithmetic circuit.

-Explanation of camera operation-
The operation of the camera 100 configured as described above will be described with reference to FIGS. FIG. 8 is a flowchart showing the operation of the camera 100 until the release button is fully pressed, and FIG. 9 is a flowchart showing the operation of the camera 100 after the release button is fully pressed.

  The following operations are mainly controlled by the body microcomputer 50.

  First, when the power switch 40a is turned on (step St1), communication between the camera body 4 and the interchangeable lens 7 is performed (step St2). Specifically, power is supplied to the body microcomputer 50 and various units in the camera body 4, and the body microcomputer 50 is activated. At the same time, electrodes are supplied to the lens microcomputer 80 and various units in the interchangeable lens 7 via the electrical sections 41a and 71a, and the lens microcomputer 80 is activated. The body microcomputer 50 and the lens microcomputer 80 are programmed to transmit and receive information to each other at the time of activation. For example, lens information relating to the interchangeable lens 7 is transmitted from the memory unit of the lens microcomputer 80 to the body microcomputer 50. 50 memory units.

  Subsequently, the body microcomputer 50 positions the focus lens group 72 at a predetermined reference position set in advance via the lens microcomputer 80 (step St3), and at the same time, opens the shutter unit 42 (see FIG. Step St4). Thereafter, the process proceeds to step St5 and waits until the photographer presses the release button 40b halfway.

  By doing so, the light that has passed through the interchangeable lens 7 and entered the camera body 4 passes through the shutter unit 42, further passes through the IR cut / OLPF 43, and enters the imaging unit 1. The subject image formed by the imaging unit 1 is displayed on the image display unit 44, and the photographer can observe an erect image of the subject via the image display unit 44. Specifically, the body microcomputer 50 reads an electrical signal from the image sensor 10 via the imaging unit control unit 52 at a constant cycle, performs predetermined image processing on the read electrical signal, and then creates an image signal. Then, the image display control unit 55 is controlled to display the live view image on the image display unit 44.

  Further, part of the light incident on the imaging unit 1 passes through the imaging element 10 and enters the phase difference detection unit 20.

  Here, when the release button 40b is half-pressed by the photographer (that is, the S1 switch (not shown) is turned on) (step St5), the body microcomputer 50 receives the signal from the line sensor 24a of the phase difference detection unit 20. After the output is amplified, it is calculated by an arithmetic circuit to detect whether it is in focus or not in focus (step St6). Furthermore, the body microcomputer 50 obtains the defocus information by obtaining the front pin or the rear pin and how much the defocus amount is (step St7). Thereafter, the process proceeds to step St10.

  Here, the phase difference detection unit 20 according to the present embodiment includes three sets of the condenser lens 21a, the mask openings 22a and 22a, the separator lens 23a, and the line sensor 24a, that is, measurement that performs focus detection by the phase difference detection method. There are three distance points. In the phase difference detection, the focus lens group 72 is driven based on the output of the set of line sensors 24a corresponding to the distance measuring points arbitrarily selected by the photographer.

  Alternatively, an automatic optimization algorithm is set in the body microcomputer 50 so that the focus lens group 72 is driven by selecting the distance measurement point closest to the camera and the subject from among the plurality of distance measurement points. Also good. In this case, it is possible to reduce the probability that a hollow photo or the like will occur.

  On the other hand, in parallel with steps St6 and St7, photometry is performed (step St8) and image blur detection is started (step St9).

  That is, in step St8, the amount of light incident on the image sensor 10 is measured by the image sensor 10. That is, in the present embodiment, since the above-described phase difference detection is performed using the light that has entered the image sensor 10 and has passed through the image sensor 10, the image sensor 10 is mounted in parallel with the phase difference detection. Can be used for photometry.

  Specifically, the body microcomputer 50 performs photometry by taking in an electrical signal from the image sensor 10 via the imaging unit controller 52 and measuring the intensity of the subject light based on the electrical signal. Then, the body microcomputer 50 determines the shutter speed and aperture value at the time of exposure according to the photographing mode from the photometric result according to a predetermined algorithm.

  Then, when the photometry is finished in step St8, image blur detection is started in step St9. Note that step St8 and step St9 may be performed in parallel.

  Thereafter, the process proceeds to step St10. In addition, after step St9, you may progress to step St12 instead of step St10.

  As described above, in the present embodiment, since the focus detection based on the above-described phase difference is performed using the light incident on the image sensor 10 and transmitted through the image sensor 10, in parallel with the focus detection, Photometry can be performed using the image sensor 10.

  In step St10, the body microcomputer 50 drives the focus lens group 72 based on the defocus information acquired in step St7.

  Then, the body microcomputer 50 determines whether or not a contrast peak has been detected (step St11). When the contrast peak is not detected (NO), the drive of the focus lens group 72 is repeated (step St10), while when the contrast peak is detected (YES), the drive of the focus lens group 72 is stopped and the focus lens group 72 is stopped. Is moved to a position where the contrast value reaches a peak, and then the process proceeds to step St11.

  Specifically, the focus lens group 72 is driven at a high speed to a position farther forward and backward than the position predicted as the in-focus position based on the defocus amount calculated in step St7. Thereafter, the contrast peak is detected while the focus lens group 72 is driven at a low speed toward the predicted position as the in-focus position.

  When the release button 40b is pressed halfway by the photographer, various information related to photographing is displayed together with the photographed image on the image display unit 44, and the photographer confirms various information via the image display unit 44. be able to.

  In step St12, the process waits until the photographer fully presses the release button 40b (that is, the S2 switch (not shown) is turned on). When the release button 40b is fully pressed by the photographer, the body microcomputer 50 temporarily closes the shutter unit 42 (step St13). Thus, while the shutter unit 42 is in the closed state, the charges accumulated in the light receiving portions 11b, 11b,...

  Thereafter, the body microcomputer 50 starts correction of image blur based on communication information between the camera body 4 and the interchangeable lens 7 or arbitrary designation information of the photographer (step St14). Specifically, the blur correction lens driving unit 74 a in the interchangeable lens 7 is driven based on information from the blur detection unit 56 in the camera body 4. Further, according to the photographer's intention, (i) the blur detection unit 84 and the blur correction lens driving unit 74a in the interchangeable lens 7 are used, and (ii) the blur detection unit 56 and the blur correction unit 45 in the camera body 4 are provided. Either (iii) using the blur detection unit 84 in the interchangeable lens 7 or the blur correction unit 45 in the camera body 4 can be selected.

  The driving of the image blur correction unit is started when the release button 40b is half-pressed, so that the movement of the subject to be focused is reduced and AF can be performed more accurately.

  In parallel with the start of image blur correction, the body microcomputer 50 narrows down the diaphragm 73 via the lens microcomputer 80 so that the diaphragm value obtained from the photometric result in step St8 is obtained (step St15).

  In this way, the correction of image blur is started, and when the narrowing is completed, the body microcomputer 50 opens the shutter unit 42 based on the shutter speed obtained from the photometric result in step St8 (step St16). Thus, by opening the shutter unit 42, the light from the subject enters the image sensor 10, and the image sensor 10 accumulates charges for a predetermined time (step St17).

  Then, the body microcomputer 50 closes the shutter unit 42 based on the shutter speed, and ends the exposure (step St18). After the exposure is completed, the body microcomputer 50 reads the image data from the imaging unit 1 via the imaging unit control unit 52, and after the predetermined image processing, the image data is sent to the image display control unit 55 via the image reading / recording unit 53. Output. As a result, the captured image is displayed on the image display unit 44. The body microcomputer 50 stores image data in the image storage unit 58 via the image recording control unit 54 as necessary.

  Thereafter, the body microcomputer 50 ends the image blur correction (step St19) and opens the diaphragm 73 (step St20). Then, the body microcomputer 50 opens the shutter unit 42 (step St21).

  When the reset is completed, the lens microcomputer 80 notifies the body microcomputer 50 of the completion of the reset. The body microcomputer 50 waits for the reset completion information from the lens microcomputer 80 and the completion of the series of processes after exposure, and then confirms that the state of the release button 40b is not depressed, and ends the photographing sequence. Thereafter, the process returns to step St5 and waits until the release button 40b is half-pressed.

  When the power switch 40a is turned off (step St22), the body microcomputer 50 moves the focus lens group 72 to a predetermined reference position set in advance (step St23) and closes the shutter unit 42. (Step St24). Then, the operation of the body microcomputer 50 and various units in the camera body 4 and the lens microcomputer 80 and various units in the interchangeable lens 7 are stopped.

  Thus, in the AF operation of this embodiment, first, the defocus information is acquired by the phase difference detection unit 20, and the focus lens group 72 is driven based on the defocus information. Then, the position of the focus lens group 72 where the contrast value calculated based on the output from the image sensor 10 reaches a peak is detected, and the focus lens group 72 is positioned at this position. In this way, since defocus information can be detected before the focus lens group 72 is driven, there is no need to drive the focus lens group 72 for the time being as in the conventional contrast detection method AF. The autofocus processing time can be shortened. In addition, since the focus is finally adjusted by the contrast detection method AF, it is possible to directly capture the contrast peak, and unlike the phase difference detection method AF, there are various methods such as open back correction (focus shift due to the aperture opening degree). Since no correction calculation is required, a highly accurate focus performance can be obtained. In particular, it is possible to focus on a subject with a repetitive pattern or a subject with extremely low contrast with higher accuracy than the conventional phase difference detection method AF.

  Since the AF operation of the present embodiment includes phase difference detection, the defocus information is acquired by the phase difference detection unit 20 using light transmitted through the image sensor 10. Metering and acquisition of defocus information by the phase difference detection unit 20 can be performed in parallel. That is, since the phase difference detection unit 20 receives the light transmitted through the image sensor 10 and acquires defocus information, the image sensor 10 is always irradiated with light from the subject when acquiring the defocus information. . Therefore, photometry is performed using light transmitted through the image sensor 10 during autofocus. By doing so, it is not necessary to separately provide a photometric sensor, and since photometry can be performed before the release button 40b is fully pressed, exposure is completed after the release button 40b is fully pressed. Time (hereinafter also referred to as a release time lag) can be shortened.

  Further, even if the photometry is performed before the release button 40b is fully pressed, it is possible to prevent the processing time after the release button 40b is half-pressed by performing photometry in parallel with the autofocus. At this time, there is no need to provide a mirror for guiding light from the subject to the photometric sensor or the phase difference detection unit.

  Conventionally, part of the light guided from the subject to the imaging device is guided to the phase difference detection unit provided outside the imaging device by a mirror or the like, whereas the light guided to the imaging unit 1 is used as it is. Since the focus state can be detected by the phase difference detection unit 20, the defocus information can be acquired with high accuracy.

  In the above-described embodiment, the so-called hybrid AF, in which the contrast AF is performed after the phase difference is detected, is adopted, but the present invention is not limited to this. For example, phase difference detection AF that performs AF based on defocus information acquired by phase difference detection may be used. Also, the hybrid AF, the phase difference detection AF, and the contrast detection AF that performs focusing based on only the contrast value without performing the phase difference detection may be switched.

-Effect of Embodiment 1-
Therefore, according to the first embodiment, the phase difference detection unit 20 configured to allow light to pass through the image sensor 10 and receive the light that has passed through the image sensor 10 and perform focus detection by the phase difference detection method is provided. And the body control unit 5 controls the image sensor 10 and performs focus adjustment by driving and controlling the focus lens group 72 based on at least the detection result of the phase difference detection unit 20, thereby using the image sensor 10. The various processes and the autofocus using the phase difference detection unit 20 can be performed in parallel, and the processing time can be shortened.

  Even if various processes using the image sensor 10 and autofocus using the phase difference detection unit 20 are not performed in parallel, according to the above configuration, when light is incident on the image sensor 10, the phase difference Since light is also incident on the detection unit 20, various processes using the image sensor 10 and autofocus using the phase difference detection unit 20 can be easily switched by switching the control of the body control unit 5. . That is, since it is not necessary to move the movable mirror forward and backward as compared with the conventional configuration in which the moving direction of the light from the subject is switched between the image pickup element and the phase difference detection unit by moving the movable mirror forward and backward, the image pickup element 10 is Since various processes used and auto-focus using the phase difference detection unit 20 can be switched immediately, and no sound is generated as the movable mirror advances and retreats, various processes and levels using the image sensor 10 can be avoided. The auto focus using the phase difference detection unit 20 can be switched silently.

  Thus, the convenience of the camera 100 can be improved.

  Specifically, the image sensor 10 is configured to allow light to pass through, and by providing the phase difference detection unit 20 that receives the light that has passed through the image sensor 10 and performs focus detection by a phase difference detection method, Like the phase difference detection AF, AF using the phase difference detection unit 20 and photometry using the image sensor 10 can be performed in parallel. By doing so, it is not necessary to perform photometry after the release button 40b is fully pressed, and the release time lag can be shortened. Further, even if the photometry is performed before the release button 40b is fully pressed, it is possible to prevent the processing time after the release button 40b is half-pressed by performing photometry in parallel with the autofocus. Furthermore, since photometry is performed using the image sensor 10, there is no need to separately provide a photometric sensor. Furthermore, there is no need to provide a movable mirror for guiding light from the subject to a photometric sensor or a phase difference detection unit. Therefore, power consumption can be suppressed.

  Further, even in the hybrid AF described above, switching from phase difference detection by the phase difference detection unit 20 to contrast detection using the image sensor 10 is performed without performing switching of an optical path using a conventional movable mirror or the like. Since it can be performed immediately by the control in the body controller 5, the time required for the hybrid AF can be shortened. Further, since the movable mirror is unnecessary, noise due to the movable mirror is eliminated and the hybrid AF can be performed silently.

  Furthermore, in the conventional configuration in which light traveling from the subject toward the image sensor 10 is directed to a phase difference detection unit disposed at a location different from the back side of the image sensor 10 using a movable mirror or the like, The focus adjustment accuracy is not high due to the difference between the optical path and the optical path at the time of phase difference detection, the installation error of the movable mirror, etc. In this embodiment, the phase difference detection unit 20 receives light passing through the image sensor 10. Since the phase difference detection method focus detection is performed, the phase difference detection method focus detection can be performed while maintaining the same optical path as that at the time of exposure, and there is no member that causes an error such as a movable mirror. Acquisition of the defocus amount based on detection can be performed with high accuracy.

  As described above, even when the image sensor 10 is configured to transmit light, the image sensor 10 can be reinforced by bonding the glass substrate 19 to the image sensor 10. That is, if the image sensor 10 is configured to transmit light, the image sensor 10 becomes very thin and the strength is reduced. Therefore, the image pickup device 10 can be reinforced by bonding the glass substrate 19 to the image pickup device 10. In the present embodiment, the glass substrate 19 is bonded to the back surface of the substrate 11a with respect to the back-illuminated imaging element 10, but the glass substrate 19 is optically transparent and transmits light. The glass substrate 19 can be prevented from obstructing the incidence of light on the image sensor 10. That is, by using the glass substrate 19, it is possible to reinforce the image sensor 10 without affecting the incidence or emission of light to the image sensor 10.

-Modification 1-
Below, the modification of this embodiment is demonstrated. FIG. 10 is a cross-sectional view of the imaging unit 210 according to the first modification.

  In the imaging unit 1, the imaging unit 1 is configured by joining the imaging element 10 and the phase difference detection unit 20 via the package 31. However, the imaging unit 201 according to the first modification includes these as semiconductors. Manufactured in process. The imaging unit 201 is the same as the imaging unit 1 with respect to the basic configuration of the imaging element 10 and the glass substrate 19. However, the protective layer 18 is not provided on the surface of the substrate 11a of the imaging device 10, and instead, the first low refractive index layer 225, the condenser lens layer 221, and the second in order from the surface of the substrate 11a. A low refractive index layer 226, a third low refractive index layer 227, a separator lens layer 223, a fourth low refractive index layer 228, and a protective layer 229 are laminated.

  The first, second, third, and fourth low refractive index layers 225, 226, 227, and 228 are made of a transparent material having a relatively low refractive index. On the other hand, the condenser lens layer 221 and the separator lens layer 223 are made of a transparent material having a relatively high refractive index. The first, second, third, and fourth low refractive index layers 225, 226, 227, and 228 may be made of the same material or different materials. Similarly, the condenser lens layer 221 and the separator lens layer 223 may be made of the same material or different materials.

  In the first low-refractive index layer 225, the bonding surface with the condenser lens layer 221 has a portion corresponding to the passage hole 14c of the emission side mask 14b provided on the substrate 11a, which is recessed toward the substrate 11a. Correspondingly, the portion of the condenser lens layer 221 that is bonded to the first low-refractive index layer 225 has a portion corresponding to the through hole 14c bulges toward the substrate 11a. That is, of the joint surface between the first low refractive index layer 225 and the condenser lens layer 221, the portion corresponding to the passage hole 14c forms a lens surface, and the condenser lens layer 221 functions as a condenser lens.

  A mask member 222 is provided on the bonding surface between the second low refractive index layer 226 and the third low refractive index layer 227. In the mask member 222, two mask openings 222a and 222a are formed at positions corresponding to the passage holes 14c.

  Further, the surface of the third low refractive index layer 227 that is bonded to the separator lens layer 223 has a concave portion on the substrate 11a side corresponding to the passage hole 14c. Specifically, the concave portion has a shape in which two concave curved surfaces are adjacent to each other. On the other hand, the joint surface of the separator lens layer 223 with the third low-refractive index layer 227 corresponds to the third low-refractive index layer 227, and a portion corresponding to the passage hole 14c is convex toward the substrate 11a. Bulges. Specifically, the convex portion has a shape in which two convex curved surfaces are adjacent to each other. That is, in the joint surface between the third low refractive index layer 227 and the separator lens layer 223, the portion corresponding to the passage hole 14c forms two lens surfaces, and the separator lens layer 223 functions as a separator lens.

  Furthermore, a line sensor 224 is provided on the joint surface between the fourth low refractive index layer 228 and the protective layer 229 at a position corresponding to the passage hole 14c.

  The first low refractive index layer 225, the condenser lens layer 221, the second low refractive index layer 226, the third low refractive index layer 227, the separator lens layer 223, the fourth low refractive index layer 228, and the protective layer 229 provide a phase difference. A detection unit 220 is configured. As described above, the glass substrate 19, the image sensor 10, and the phase difference detection unit 220 may be manufactured by a semiconductor process.

-Modification 2-
Next, an image sensor 310 according to Modification 2 will be described with reference to FIG. FIG. 11 is a cross-sectional view of the image sensor 310.

  Unlike the image sensor 10 that is a CCD image sensor, the image sensor 310 is a CMOS image sensor. Specifically, the imaging element 310 includes a photoelectric conversion unit 311 made of a semiconductor material, a transistor 312, a signal line 313, a mask 314, and a color filter 315.

  The photoelectric conversion unit 311 includes a substrate 311a and light receiving units 311b, 311b,. A transistor 312 is provided for each light receiving unit 311b. The charge accumulated in the light receiving portion 311b is amplified by the transistor 312 and output to the outside through the signal line 313.

  Like the mask 14, the mask 314 includes an incident side mask 314a and an emission side mask 314b. The incident side mask 314 a is provided adjacent to the light receiving portion 311 b and prevents light from entering the transistor 312 and the signal line 313. Further, the emission side mask 314b is provided with a plurality of passage holes 314c for emitting the light transmitted through the light receiving portion 311b to the back side of the image sensor 310.

  The color filter 315 has the same configuration as the color filter 15.

  In the CMOS image sensor, since the amplification factor of the transistor 312 can be set for each light receiving portion 311b, whether or not each light receiving portion 311b is positioned at a position corresponding to the passage hole 314c. Or setting based on the color type of the color filter 315 corresponding to each light receiving portion 311b, thereby preventing the image of the portion corresponding to the through holes 314c, 314c,. Can do.

-Modification 3-
Next, an imaging unit 401 according to Modification 3 will be described with reference to FIGS. FIG. 12 is a cross-sectional view of the image sensor 410 of the image pickup unit 401, and FIG. 13 is a cross-sectional view showing a state in which the image sensor 410 is attached to the circuit board 432.

  The imaging unit 401 differs from the imaging unit 1 in that light from a subject is incident on the front surface, not the back surface of the substrate of the image sensor. Therefore, the same components as those of the imaging unit 1 are denoted by the same reference numerals, description thereof is omitted, and different components are mainly described.

  The imaging unit 401 includes an imaging element 410 for converting a subject image into an electrical signal, a glass substrate 19 bonded to the imaging element 410, a package for holding the imaging element 410, and phase difference detection type focus detection. A phase difference detection unit for performing the above. The package and the phase difference detection unit have the same configuration as that of the imaging unit 1 although not shown.

  The imaging element 410 is a back-illuminated interline CCD image sensor, and as shown in FIG. 12, a photoelectric conversion unit 11 made of a semiconductor material, a vertical register 12, a transfer path 13, and a mask 414. And a color filter 15 and a microlens 416.

  On the surface of the substrate 11a, light receiving portions 11b, 11b,... Are provided in minute square pixel regions arranged in a matrix. A vertical register 12 is provided on the surface of the substrate 11a adjacent to each light receiving portion 11b. Further, a transfer path 13 is provided so as to overlap the vertical register 12. A mask 414 is provided so as to cover the vertical register 12 and the transfer path 13.

  Unlike the mask 14 according to the imaging unit 1, the mask 414 is provided only on the incident side of light from the subject. Specifically, the mask 414 is provided so as to cover the vertical register 12 and the transfer path 13 from the side opposite to the substrate 11a. Thus, the mask 414 prevents light from the subject side from entering the vertical register 12 and the transfer path 13.

  Further, a protective layer 18 made of an optically transparent resin is provided on the surface of the substrate 11a so as to cover the light receiving portion 11b, the vertical register 12, the transfer path 13, and the mask 414.

  The color filter 15 is laminated on the surface of the protective layer 18 (that is, the surface of the protective layer 18 opposite to the substrate 11a). The color filter 15 is a color filter containing a dye system or a pigment system pigment.

  The microlens 416 is made of an optically transparent resin, collects light and makes it incident on the light receiving unit 11 b, and is stacked on the color filter 15. Specifically, the microlens 416 is a convex lens that is provided for each light receiving unit 11b, that is, for each color filter 15, and bulges in a convex shape on the subject side (that is, the side opposite to the substrate 11a). The microlens 416 can efficiently irradiate the light receiving portion 11b.

  Further, a protective layer 17 made of an optically transparent resin is laminated on the surface (convex surface) of the microlens 416.

  The glass substrate 19 is bonded to the back surface of the substrate 11a by anodic bonding.

  In the imaging device 10 configured as described above, the light collected by the microlenses 416, 416,... Enters the color filters 15r, 15g, and 15b, and only the light of the color corresponding to each color filter 15 is obtained. The light passes through the color filter 15 and reaches the surface of the substrate 11a. In the substrate 11a, only the light receiving portions 11b, 11b,... Are exposed, and the vertical register 12, the transfer path 13, and the like are covered with the mask 414. Therefore, the light reaching the substrate 11a is directed to the light receiving portions 11b, 11b,. Only incident. Each light receiving portion 11b absorbs light and generates electric charges. The electric charge generated in each light receiving unit 11b is sent to the amplifier via the vertical register 12 and the transfer path 13 and is output as an electric signal. At this time, since light of a specific color transmitted through the color filters 15r, 15g, and 15b is incident on the light receiving portions 11b, 11b,..., The colors corresponding to the color filters 15 are received from the light receiving portions 11b. The received light quantity is obtained as an output. Thus, the image sensor 410 converts the subject image formed on the imaging surface into an electrical signal by performing photoelectric conversion at the light receiving portions 11b, 11b,... On the entire imaging surface.

  On the other hand, a part of the light incident on the light receiving part 11b is not absorbed by the light receiving part 11b but passes through the light receiving part 11b. Since the substrate 11a is very thin (that is, the substrate 11a is formed to have a thickness that allows light to pass through), the light transmitted through the light receiving portion 11b passes through the substrate 11a, and further, the glass substrate 19 Is transmitted to the back side of the image sensor 410.

  Similar to the imaging unit 1, a phase difference detection unit is provided on the back side of the imaging element 410, and the phase difference detection unit uses the light transmitted through the imaging element 410 to detect the focus of the phase difference detection method. I do.

  The imaging element 410 configured as described above is mounted on the circuit board 432 of the package.

  Specifically, the light receiving portion 11b, the vertical register 12, the transfer path 13, the mask 414, the color filter 15, the microlens 416, the protective layers 17 and 18 and the like are not provided on the peripheral portion of the substrate 11a of the image sensor 410. The wiring for enabling electrical connection with the transfer path 13 and the vertical register 12 is exposed. On the other hand, a circuit pattern is provided on the back surface (the surface opposite to the subject) of the circuit board 432 at a position facing the wiring of the substrate 11 a of the image sensor 410. Then, as shown in FIG. 13, the peripheral portion of the substrate 11a of the image sensor 410 is overlapped with the circuit board 432 from the opposite side to the subject, and the two are joined by thermal welding to connect the wiring of the substrate 11a of the image sensor 410. The circuit pattern of the circuit board 432 is electrically connected.

  Therefore, even when the image sensor 410 is configured to transmit light, the image sensor 410 can be reinforced by bonding the glass substrate 19 to the image sensor 410. That is, if the image sensor 410 is configured to transmit light, the image sensor 410 becomes very thin and the strength is reduced. Therefore, the image pickup element 410 can be reinforced by bonding the glass substrate 19 to the image pickup element 410. And in the structure which makes light inject from the surface of the board | substrate 11a instead of back surface irradiation, although the glass substrate 19 is joined to the back surface of the board | substrate 11a, this glass substrate 19 is optically transparent and permeate | transmits light. Therefore, it is possible to prevent the glass substrate 19 from interfering with the emission of light from the image sensor 410. That is, by using the glass substrate 19, it is possible to reinforce the image sensor 410 without affecting the emission of light from the image sensor 410.

  In addition, the same effects as the imaging unit 1 can be achieved.

<< Embodiment 2 of the Invention >>
Next, an imaging unit 501 according to Embodiment 2 of the present invention will be described with reference to FIG. FIG. 14 is a cross-sectional view of the image sensor 510 of the imaging unit 501.

  An imaging unit 501 according to the second embodiment is different from the first embodiment in that it does not include a phase difference detection unit. Therefore, configurations similar to those of the first embodiment are denoted by the same reference numerals, description thereof is omitted, and different configurations are mainly described.

  The imaging unit 501 includes an imaging element 510 for converting a subject image into an electrical signal, and a glass substrate 19 bonded to the imaging element 510.

  The configuration of the image sensor 510 is the same as that of the first embodiment except for the configuration of the emission side mask 514b. That is, the mask 514 includes an incident side mask 514a provided on the surface of the substrate 11a, and an emission side mask 514b provided so as to cover the light receiving unit 11b, the vertical register 12, and the transfer path 13 from the side opposite to the substrate 11a. have. The emission side mask 514b is not provided with a passage hole, and completely covers the light receiving unit 11b, the vertical register 12, and the transfer path 13 from the side opposite to the substrate 11a.

  In the imaging device 510 configured as described above, all the light transmitted through the light receiving portions 11b, 11b,... Is reflected by the emission side mask 514b, and is incident again on the light receiving portions 11b, 11b,. Are not emitted to the back side of the image sensor 510.

  That is, the image sensor 510 according to the second embodiment is a back-illuminated image sensor and does not perform phase difference detection. As described above, regardless of whether or not the phase difference detection type focus detection is performed, as long as the imaging device is a back-illuminated type, it is necessary to allow the light to pass through the substrate 11a. In the configuration in which light is transmitted through the substrate 11a, it is necessary to form the substrate 11a thin enough to transmit light. As described above, by bonding the glass substrate 19 to the image sensor 510, the image sensor 510 is provided. The image pickup element 510 can be reinforced without affecting the incidence of light.

<< Other Embodiments >>
The present invention may be configured as follows with respect to the above embodiment.

  For example, the configuration of the image sensor is not limited to the above configuration, and any configuration can be adopted as long as light is transmitted through the image sensor. Further, the phase difference detection unit is not limited to the above configuration.

  Moreover, joining of an image pick-up element and an optical transparent substrate may be implement | achieved by forming an image pick-up element on an optical transparent substrate, for example.

  Moreover, although the said embodiment demonstrated the structure which mounted the imaging unit 1 in the camera, it is not restricted to this. For example, the imaging unit 1 can be mounted on a video camera.

  In addition, the configuration is described in which AF is started when the photographer presses the release button 40b halfway (that is, when the S1 switch is turned on). However, even if the release button 40b is subjected to AF before halfway pressing. Good. Further, although the configuration has been described in which AF is terminated when it is determined that the focus is achieved, AF may be continued after the focus determination, or AF may be performed continuously without performing the focus determination.

  In the above-described embodiment, the substrate 11a may be completely removed by polishing, etching, or the like. In that case, the glass substrate 19 may be directly joined to the light receiving part 11b. In addition, the light receiving portion 11 b may be directly formed on the glass substrate 19.

  In addition, the above embodiment is an essentially preferable illustration, Comprising: It does not intend restrict | limiting the range of this invention, its application thing, or its use.

  As described above, the present invention is useful for an imaging unit including an imaging device that performs photoelectric conversion.

1, 201, 401, 501 Imaging unit 10, 310, 410 Imaging element 11a Substrate (semiconductor substrate)
11b Light receiver 15 Color filter (interference filter)
20,220 Phase difference detection unit (phase difference detection unit)
21a condenser lens 221 condenser lens layer (condenser lens)
23a Separator lens 223 Separator lens layer (Separator lens)
24a, 224 line sensor 31 package

  The present invention relates to an imaging unit including an imaging device that performs photoelectric conversion.

  2. Description of the Related Art In recent years, digital cameras that convert an object image into an electrical signal using an imaging device such as a charge coupled device (CCD) image sensor or a complementary metal-oxide semiconductor (CMOS) image sensor and digitize and record the electrical signal have been developed. It is popular.

  A digital single-lens reflex camera has a phase difference detection unit that detects a phase difference of a subject image, and thus has a phase difference detection AF function that performs autofocus (hereinafter also simply referred to as AF). According to the phase difference detection AF function, the defocus direction and the defocus amount can be detected, so that the moving time of the focus lens can be shortened and the focus can be quickly achieved (for example, Patent Document 1). In a conventional digital single lens reflex camera, in order to guide light from a subject to a phase difference detection unit, a movable mirror configured to be able to advance / retreat on an optical path from a lens barrel to an image sensor is provided.

  A so-called compact digital camera adopts an autofocus function by video AF using an image sensor (for example, Patent Document 2). In this way, the compact digital camera is miniaturized by eliminating the mirror for guiding the light from the subject to the phase difference detection unit. In such a compact digital camera, autofocus can be performed while exposing the image sensor. That is, while performing autofocus, various processes using the image sensor, for example, obtaining an image signal from a subject image formed on the image sensor and displaying it on the image display unit provided on the back of the camera, It can be recorded in the recording unit. This autofocus function by video AF is generally advantageous in that it has higher accuracy than phase difference detection AF.

JP 2007-163545 A JP 2007-135140 A

  However, the video AF cannot detect the defocus direction instantaneously like the digital camera according to Patent Document 2. For example, according to the contrast detection method AF, the focus is detected by detecting the contrast peak, but if the focus lens is not moved back and forth from the current position, the direction of the contrast peak, that is, the defocus direction is detected. Can not do it. Therefore, it takes time for focus detection.

  That is, the phase difference detection method AF is more advantageous from the viewpoint of reducing the time required for focus detection. However, in an imaging apparatus that employs phase difference detection AF such as a digital single-lens reflex camera according to Patent Document 1, in order to guide light from a subject to a phase difference detection unit, the lens barrel is moved to the imaging device. It is necessary to move a movable mirror on the optical path. Therefore, various processes using the image sensor cannot be performed while performing the phase difference detection method AF. Further, when the path of incident light is switched between the path toward the phase difference detection unit and the path toward the image sensor, it is necessary to move the movable mirror, and a time lag and noise for the movement of the movable mirror are generated.

  That is, the conventional imaging apparatus that performs the phase difference detection method AF is not convenient due to various processes using the imaging element.

  The present invention has been made in view of such a point, and the object of the present invention is to provide convenience in performing various processes using an image sensor and phase difference detection using a phase difference detection unit. It is to improve.

  As a result of intensive studies, the applicant of the present application has found that light transmitted through the image sensor is used in order to solve the above problems. That is, by performing focus detection by the phase difference detection method using light transmitted through the image sensor, the movable mirror can be eliminated, and processing by the image sensor and phase difference detection can be performed in parallel. Furthermore, by allowing light to pass through the image sensor, not only the phase difference detection but also convenience in performing various processes can be improved.

  However, in order to allow light to pass through the image sensor, it is necessary to form the image sensor thin, and this reduces the strength of the image sensor. That is, an object of the present invention is to provide an imaging unit capable of ensuring the strength of the image sensor while allowing the image sensor to transmit light.

  Therefore, the present invention reinforces the image sensor by bonding an optically transparent substrate to the substrate of the image sensor. Specifically, an imaging unit according to the present invention has a semiconductor substrate and a light receiving portion provided on the semiconductor substrate, converts light received by the light receiving portion into an electrical signal by photoelectric conversion, An imaging element configured to transmit light and an optically transparent substrate that is bonded to the imaging element and transmits light are provided.

  According to the present invention, even if an image pickup device is formed thin enough to transmit light by bonding an optical transmission substrate to the image pickup device, the image pickup device can be reinforced. By configuring the reinforcing substrate with an optically transparent substrate, the optically transparent substrate can also transmit light. Therefore, when light enters or exits the image sensor, the optical substrate It is possible to prevent the transparent substrate from interfering with the incidence or emission of the light.

FIG. 1 is a cross-sectional view of the image sensor according to the first embodiment. FIG. 2 is a block diagram of the camera. FIG. 3 is a cross-sectional view of the imaging unit. FIG. 4 is a plan view of the image sensor. FIG. 5 is a partially enlarged cross-sectional view showing a joint portion between the image sensor and the package. FIG. 6 is a plan view of the phase detection unit. FIG. 7 is a perspective view of the imaging unit. FIG. 8 is a flowchart showing the photographing operation until the release button is fully pressed. FIG. 9 is a flowchart showing the photographing operation after the release button is fully pressed. FIG. 10 is a cross-sectional view of an imaging unit according to the first modification. FIG. 11 is a cross-sectional view of an image sensor according to the second modification. FIG. 12 is a cross-sectional view of an image sensor according to the third modification. FIG. 13 is a cross-sectional view illustrating the bonding between the image sensor and the package according to the third modification. FIG. 14 is a cross-sectional view of the image sensor according to the second embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

Embodiment 1 of the Invention
A camera including the imaging unit 1 according to Embodiment 1 of the present invention will be described.

  As shown in FIG. 2, the camera 100 according to the first embodiment is an interchangeable-lens single-lens reflex digital camera. The camera 100 mainly has a main function of the camera system, and is removable from the camera body 4. The interchangeable lens 7 is mounted. The interchangeable lens 7 is attached to a body mount 41 provided on the front surface of the camera body 4. The body mount 41 is provided with an electrical section 41a.

-Camera body configuration-
The camera body 4 has an imaging unit 1 that acquires a subject image as a captured image, a shutter unit 42 that adjusts the exposure state of the imaging unit 1, and infrared light removal and moire phenomenon of the subject image incident on the imaging unit 1. And an image display unit 44 that includes an IR cut and OLPF (Optical Low Pass Filter) 43, a liquid crystal monitor, and displays captured images, live view images, and various types of information, and a body control unit 5. . This camera body 4 constitutes the imaging apparatus body.

  The camera body 4 is provided with a power switch 40a that operates to turn on / off the power of the camera system, and a release button 40b that is operated by the photographer during focusing and release.

  When the power is turned on by the power switch 40 a, power is supplied to each part of the camera body 4 and the interchangeable lens 7.

  The release button 40b is a two-stage type, and performs autofocus and AE, which will be described later, when pressed halfway, and releases when pressed fully.

  As will be described in detail later, the imaging unit 1 converts the subject image into an electrical signal by photoelectric conversion. The imaging unit 1 is configured to be movable in a plane perpendicular to the optical axis X by the blur correction unit 45.

  The body control unit 5 controls the operation of the body microcomputer 50, the nonvolatile memory 50 a, the shutter control unit 51 that controls the driving of the shutter unit 42, and the imaging unit 1, and converts the electrical signal from the imaging unit 1 to A / The imaging unit control unit 52 that performs D conversion and outputs the image data to the body microcomputer 50, and the reading of the image data from the image storage unit 58, which is a card-type recording medium or an internal memory, for example, and the recording of the image data in the image storage unit 58 The image reading / recording unit 53 to perform, the image recording control unit 54 for controlling the image reading / recording unit 53, the image display control unit 55 for controlling the display of the image display unit 44, and the image blur caused by the camera body 4 blur A blur detection unit 56 that detects the amount and a correction unit control unit 57 that controls the blur correction unit 45 are included. This body control part 5 comprises a control part.

  The body microcomputer 50 is a control device that controls the center of the camera body 4 and controls various sequences. For example, a CPU, a ROM, and a RAM are mounted on the body microcomputer 50. And the body microcomputer 50 can implement | achieve various functions because the program stored in ROM is read by CPU.

  The body microcomputer 50 receives input signals from the power switch 40a and the release button 40b, as well as a shutter control unit 51, an imaging unit control unit 52, an image readout / recording unit 53, an image recording control unit 54, and a correction unit control. The controller 57 is configured to output control signals to the shutter 57, the imaging unit controller 52, the image reading / recording unit 53, the image recording controller 54, the correction unit controller 57, and the like. Make control run. The body microcomputer 50 performs inter-microcomputer communication with a lens microcomputer 80 described later.

  For example, in accordance with an instruction from the body microcomputer 50, the imaging unit control unit 52 performs A / D conversion on the electrical signal from the imaging unit 1 and outputs it to the body microcomputer 50. The body microcomputer 50 performs predetermined image processing on the captured electric signal to create an image signal. The body microcomputer 50 transmits an image signal to the image reading / recording unit 53 and instructs the image recording control unit 54 to record and display an image, and stores the image signal in the image storage unit 58 and the image. The image signal is transmitted to the display control unit 55. The image display control unit 55 controls the image display unit 44 based on the transmitted image signal, and causes the image display unit 44 to display an image.

  Various information (main body information) related to the camera body 4 is stored in the nonvolatile memory 50a. The body information includes, for example, the model name for identifying the camera body 4 such as the manufacturer name, date of manufacture, model number, software version installed in the body microcomputer 50, and information on the firmware upgrade. Information (main body specifying information), information about whether the camera body 4 is equipped with means for correcting image blur such as the blur correction unit 45 and the blur detection unit 56, the model number and sensitivity of the blur detection unit 56, etc. It also includes information on detection performance, error history, etc. These pieces of information may be stored in the memory unit in the body microcomputer 50 instead of the nonvolatile memory 50a.

  The shake detection unit 56 includes an angular velocity sensor that detects the movement of the camera body 4 caused by camera shake or the like. The angular velocity sensor outputs a positive / negative angular velocity signal according to the direction in which the camera body 4 moves with reference to the output when the camera body 4 is stationary. In the present embodiment, two angular velocity sensors are provided to detect the two directions of the yawing direction and the pitching direction. The output angular velocity signal is subjected to filter processing, amplifier processing, and the like, converted into a digital signal by an A / D conversion unit, and provided to the body microcomputer 50.

-Composition of interchangeable lens-
The interchangeable lens 7 constitutes an imaging optical system for connecting a subject image to the imaging unit 1 in the camera body 4, and mainly includes a focus adjustment unit 7A that performs focusing and an aperture adjustment unit 7B that adjusts the aperture. The image blur correction unit 7C for correcting the image blur by adjusting the optical path and the lens control unit 8 for controlling the operation of the interchangeable lens 7 are provided.

  The interchangeable lens 7 is attached to the body mount 41 of the camera body 4 via the lens mount 71. In addition, the lens mount 71 is provided with an electrical piece 71 a that is electrically connected to the electrical piece 41 a of the body mount 41 when the interchangeable lens 7 is attached to the camera body 4.

  The focus adjustment unit 7A includes a focus lens group 72 that adjusts the focus. The focus lens group 72 is movable in the direction of the optical axis X in a section from the closest focus position to the infinite focus position defined as the standard of the interchangeable lens 7. In addition, the focus lens group 72 needs to be movable back and forth in the optical axis X direction with respect to the focus position in the case of focus position detection by a contrast detection method to be described later. It has a lens shift margin section that can move further back and forth in the optical axis X direction than the section to the infinite focus position. The focus lens group 72 does not necessarily need to be composed of a plurality of lenses, and may be composed of a single lens.

  The diaphragm adjustment unit 7B is configured by a diaphragm unit 73 that adjusts the diaphragm or opening. The diaphragm 73 constitutes a light quantity adjustment unit.

  The lens image blur correction unit 7C includes a blur correction lens 74 and a blur correction lens driving unit 74a that moves the blur correction lens 74 in a plane perpendicular to the optical axis X.

  The lens controller 8 receives a control signal from the lens microcomputer 80, the nonvolatile memory 80 a, the focus lens group controller 81 that controls the operation of the focus lens group 72, and the focus lens group controller 81, and receives the focus lens group 72. A focus drive unit 82 for driving the lens, a diaphragm control unit 83 for controlling the operation of the diaphragm unit 73, a blur detection unit 84 for detecting blur of the interchangeable lens 7, and a blur correction lens unit for controlling the blur correction lens driving unit 74a. And a control unit 85.

  The lens microcomputer 80 is a control device that controls the center of the interchangeable lens 7, and is connected to each unit mounted on the interchangeable lens 7. Specifically, the lens microcomputer 80 is equipped with a CPU, a ROM, and a RAM, and various functions can be realized by reading a program stored in the ROM into the CPU. For example, the lens microcomputer 80 has a function of setting a lens image blur correction device (such as the blur correction lens driving unit 74a) to a correctable state or an uncorrectable state based on a signal from the body microcomputer 50. Further, the body microcomputer 50 and the lens microcomputer 80 are electrically connected by contact between the electrical slice 71a provided on the lens mount 71 and the electrical slice 41a provided on the body mount 41, so that information can be transmitted and received between them. It has become.

  In addition, various information (lens information) related to the interchangeable lens 7 is stored in the nonvolatile memory 80a. The lens information includes, for example, a model for specifying the interchangeable lens 7 such as a manufacturer name, a date of manufacture, a model number, a software version installed in the lens microcomputer 80, and information on firmware upgrade of the interchangeable lens 7. Information (lens specifying information), information on whether or not the interchangeable lens 7 is equipped with means for correcting image blur such as the blur correction lens driving unit 74a and blur detection unit 84, and means for correcting image blur , Information on the detection performance such as the model number and sensitivity of the blur detection unit 84, information on the correction performance such as the model number of the blur correction lens driving unit 74a and the maximum correctable angle (lens side correction performance information), Software version for image blur correction is included. Further, the lens information includes information on power consumption necessary for driving the blur correction lens driving unit 74a (lens side power consumption information) and information on driving method of the blur correction lens driving unit 74a (lens side driving method information). It is. The nonvolatile memory 80a can store information transmitted from the body microcomputer 50. These pieces of information may be stored in a memory unit in the lens microcomputer 80 instead of the nonvolatile memory 80a.

  The focus lens group control unit 81 includes an absolute position detection unit 81a that detects an absolute position of the focus lens group 72 in the optical axis direction, and a relative position detection unit 81b that detects a relative position of the focus lens group 72 in the optical axis direction. Have. The absolute position detector 81 a detects the absolute position of the focus lens group 72 in the casing of the interchangeable lens 7. The absolute position detector 81a is constituted by, for example, a contact encoder board of several bits and a brush, and is configured to be able to detect the absolute position. The relative position detector 81b alone cannot detect the absolute position of the focus lens group 72, but can detect the moving direction of the focus lens group 72, and uses, for example, a two-phase encoder. Two two-phase encoders, such as a rotary pulse encoder, an MR element, and a Hall element, are provided that alternately output binary signals at an equal pitch according to the position of the focus lens group 72 in the optical axis direction. These pitches are installed so as to shift the phases. The lens microcomputer 80 calculates the relative position of the focus lens group 72 in the optical axis direction from the output of the relative position detector 81b.

  The shake detection unit 84 includes an angular velocity sensor that detects the movement of the interchangeable lens 7 caused by camera shake or the like. The angular velocity sensor outputs positive and negative angular velocity signals according to the direction in which the interchangeable lens 7 moves with reference to the output when the interchangeable lens 7 is stationary. In the present embodiment, two angular velocity sensors are provided to detect the two directions of the yawing direction and the pitching direction. The output angular velocity signal is subjected to filter processing, amplifier processing, and the like, converted into a digital signal by an A / D conversion unit, and provided to the lens microcomputer 80.

  The blur correction lens unit control unit 85 includes a movement amount detection unit (not shown). The movement amount detection unit is a detection unit that detects an actual movement amount of the blur correction lens 74. The blur correction lens unit control unit 85 performs feedback control of the blur correction lens 74 based on the output from the movement amount detection unit.

  Although an example in which the camera shake detection units 56 and 84 and the camera shake correction devices 45 and 74a are mounted on both the camera body 4 and the interchangeable lens 7 has been shown, A correction device may be mounted, and neither of the shake detection unit and the shake correction device may be mounted (in this case, the above-described sequence related to the shake correction may be excluded).

-Image unit configuration-
As shown in FIG. 3, the imaging unit 1 includes an imaging element 10 for converting a subject image into an electrical signal, a glass substrate 19 bonded to the imaging element 10, and a package 31 for holding the imaging element 10. And a phase difference detection unit 20 for performing focus detection by the phase difference detection method.

  The imaging device 10 is a back-illuminated interline CCD image sensor, and as shown in FIG. 1, a photoelectric conversion unit 11 made of a semiconductor material, a vertical register 12, a transfer path 13, and a mask 14 And a color filter 15.

  The photoelectric conversion unit 11 includes a substrate 11a and a plurality of light receiving units (also referred to as pixels) 11b, 11b,... Arranged on the substrate 11a.

The substrate 11a is a semiconductor substrate composed of Si (silicon) base. Specifically, the substrate 11a is formed of a Si single crystal substrate or an SOI (Silicon On Insulator wafer). In particular, the SOI substrate has a sandwich structure of an Si thin film and an SiO ₂ thin film, and can stop the reaction in the SiO ₂ layer in an etching process or the like, which is advantageous for stable substrate processing.

  The light receiving portion 11b is composed of a photodiode and absorbs light to generate charges. The light receiving portions 11b, 11b,... Are respectively provided in minute square pixel regions arranged in a matrix on the surface of the substrate 11a (the lower surface in FIG. 1) (see FIG. 4).

  As described above, the imaging element 10 is a back-illuminated type, and the light from the subject is on the opposite side of the surface (hereinafter also referred to as the front surface) on the substrate 11a where the light receiving portions 11b, 11b,. Incident from the surface (hereinafter also referred to as the back surface).

  The vertical register 12 is provided for each light receiving portion 11b on the front surface side of the substrate 11a, and has a role of temporarily storing charges accumulated in the light receiving portion 11b. That is, the electric charge accumulated in the light receiving unit 11 b is transferred to the vertical register 12. The charges transferred to the vertical register 12 are transferred to a horizontal register (not shown) via the transfer path 13 and sent to an amplifier (not shown). The electric charge sent to the amplifier is amplified and taken out as an electric signal.

  The mask 14 includes an incident-side mask 14a provided on the surface of the substrate 11a, and an emission-side mask 14b provided so as to cover the light receiving unit 11b, the vertical register 12, and the transfer path 13 from the side opposite to the substrate 11a. is doing. The incident side mask 14a is provided between the light receiving portions 11b and 11b on the surface of the substrate 11a. The vertical register 12 and the transfer path 13 are provided so as to overlap the incident side mask 14a. In this way, the incident side mask 14 a prevents the light transmitted through the substrate 11 a from entering the vertical register 12 and the transfer path 13. The emission side mask 14b reflects the light transmitted through the light receiving parts 11b, 11b,... Without being absorbed by the light receiving parts 11b, 11b,. In addition, a plurality of through holes 14c (FIG. 1) for emitting light that has passed through the light receiving portion 11b to the back side of the image sensor 10 (in the present embodiment, the side opposite to the glass substrate 19) is provided in the emission side mask 14b. , Only one is shown). Note that the emission side mask 14b may not be provided.

  A protective layer 18 made of an optically transparent resin is provided on the surface of the substrate 11a so as to cover the light receiving portion 11b, the vertical register 12, the transfer path 13, and the mask 14.

  The color filter 15 is provided for each of the small square pixel regions corresponding to each light receiving portion 11b on the back side of the substrate 11a. The color filter 15 is for transmitting only a specific color, and is a thin film interference filter formed of a dielectric. In this embodiment, as shown in FIG. 4, a so-called Bayer type primary color filter is used. That is, for the entire image sensor 10, when four color filters 15, 15,... (Or four pixel regions) adjacent to 2 rows and 2 columns are defined as one repeating unit, Two green color filters (that is, color filters having higher transmittance than the visible light wavelength region of colors other than green with respect to the green visible light wavelength region) 15g are arranged in the diagonal direction, A diagonally red color filter (that is, a color filter having a higher transmittance than the visible light wavelength range of colors other than red with respect to the red visible light wavelength range) 15r and a blue color filter (that is, And a color filter 15b having a higher transmittance than the visible light wavelength region of colors other than blue with respect to the blue visible light wavelength region. As a whole, every other green color filter 15g, 15g,... Is arranged vertically and horizontally. The color filter 15 may be a complementary color filter that transmits each color of CyMYG. The color filter 15 is vapor-deposited on the bonding surface of the glass substrate 19 with the image sensor 10.

  The glass substrate 19 is composed of a borosilicate glass substrate. This glass substrate 19 corresponds to an optically transparent substrate. The glass substrate 19 is anodically bonded to the substrate 11a. Here, since borosilicate glass is rich in mobile ions, anodic bonding with the substrate 11a is possible by configuring the glass substrate 19 with borosilicate glass. Further, as described above, the color filter 15 is deposited on the surface of the glass substrate 19 to be bonded to the substrate 11a. Since the color filter 15 is a dielectric, the glass substrate 19 is attached to the substrate 11a as an anode. Can be joined.

  As a material of the glass substrate 19, for example, Pyrex (registered trademark) manufactured by Corning, or Tempax Duran manufactured by Schott can be employed. Further, the bonding between the glass substrate 19 and the substrate 11a is not limited to the anodic bonding, and may be bonding via an adhesive or the like.

Here, the substrate 11a to be anodically bonded to the glass substrate 19 may be anodically bonded to the glass substrate 19 after being polished to a desired thickness (for example, 1 to 5 μm) or thicker than the desired thickness. After the substrate 11a is anodically bonded, it may be polished to a desired thickness by etching or the like. When the substrate 11a thicker than the desired thickness is used, the substrate 11a that has been anodically bonded is heat-treated to form a SiO ₂ layer on the surface of the substrate 11a opposite to the glass substrate 19. Then, a thin (eg, 1 to 2 μm) Si layer is formed by dissolving only the SiO ₂ layer with hydrofluoric acid. At the same time, the light receiving portion 11b, the vertical register 12, the transfer path 13 and the like are formed in the Si layer by a semiconductor process.

  In the imaging device 10 configured as described above, light enters from the glass substrate 19 side. Specifically, light that has passed through the glass substrate 19 is incident on the color filters 15r, 15g, and 15b, and only light of a color corresponding to each color filter 15 is transmitted through the color filter 15 and incident on the back surface of the substrate 11a. To do. Since the substrate 11a is very thin (that is, the substrate 11a is formed to have a thickness that allows light to pass through), the light incident on the substrate 11a passes through the substrate 11a and reaches the surface of the substrate 11a. It reaches the arranged light receiving portions 11b, 11b,. Here, since the incident side mask 14a is provided in the region where the light receiving portions 11b, 11b,... Are not provided on the surface of the substrate 11a, no light enters the vertical register 12 or the transfer path 13. . In addition, the light receiving portions 11b, 11b,... Have a very high quantum efficiency because the entire surface is open to the light incident side (substrate 11a side) unlike the image sensor 410 of the second embodiment described later. Become. Each light receiving portion 11b absorbs light and generates electric charges. Here, since the emission side mask 14b is provided on the opposite side of the light receiving portion 11b from the substrate 11a, the light transmitted through the light receiving portion 11b without being absorbed by the light receiving portion 11b is transmitted to the emission side mask. The light is reflected by 14b and enters the light receiving unit 11b again. By doing so, the quantum efficiency can be further increased. The electric charge generated in each light receiving unit 11b is sent to the amplifier via the vertical register 12 and the transfer path 13 and is output as an electric signal. At this time, since light of a specific color transmitted through the color filters 15r, 15g, and 15b is incident on the light receiving portions 11b, 11b,..., The colors corresponding to the color filters 15 are received from the light receiving portions 11b. The received light quantity is obtained as an output.

  Thus, the image sensor 10 converts the subject image formed on the imaging surface into an electrical signal by performing photoelectric conversion at the light receiving portions 11b, 11b,... On the entire imaging surface.

  The imaging device 10 configured in this way is held in a package 31 (see FIG. 3). The package 31 constitutes a holding unit.

  Specifically, the package 31 is provided with a circuit board 32 on a flat bottom plate 31a, and with standing walls 31b, 31b,. The image sensor 10 is mounted on the circuit board 32 so as to be covered on all sides by the standing walls 31b, 31b,.

  Specifically, as shown in FIG. 5, the light receiving unit 11 b, the vertical register 12, the transfer path 13, the mask 14, the protective layer 18, and the like are not provided at the peripheral edge of the substrate 11 a of the image sensor 10. 13 and the wiring for enabling electrical connection with the vertical register 12 and the like are exposed.

  On the other hand, the circuit board 32 has a board base 32a, and a circuit pattern 32b is provided on the surface (subject side surface) of the board base 32a at a position facing the wiring of the board 11a of the image sensor 10. . Then, the peripheral portion of the substrate 11a of the image sensor 10 is overlapped with the circuit board 32 from the subject side, and both are joined by thermal welding to electrically connect the wiring of the substrate 11a of the image sensor 10 and the circuit pattern 32b. is doing.

  Further, a cover glass 33 is attached to the tips of the standing walls 31b, 31b,... Of the package 31 so as to cover the imaging surface (back surface) of the imaging device 10. The cover glass 33 protects the image pickup surface of the image pickup device 10 from dust and the like.

  Here, the bottom plate 31a of the package 31 has the same number as the passage holes 14c, 14c,... In the position corresponding to the passage holes 14c, 14c,. ), The openings 31c, 31c,. Through the openings 31c, 31c,..., The light transmitted through the image sensor 10 reaches a phase difference detection unit 20 described later.

  Note that the opening 31 c is not necessarily formed through the bottom plate 31 a of the package 31. That is, as long as the light transmitted through the image sensor 10 reaches the phase difference detection unit 20, a configuration such as forming a transparent portion or a semi-transparent portion on the bottom plate 31a may be used.

  The phase difference detection unit 20 is provided on the back side (opposite to the subject) of the image sensor 10 and receives the transmitted light from the image sensor 10 to perform focus detection by the phase difference detection method. Specifically, the phase difference detection unit 20 converts the received transmitted light into an electric signal for distance measurement. This phase difference detection unit 20 constitutes a phase difference detection unit.

  3 and 6, the phase difference detection unit 20 includes a condenser lens unit 21, a mask member 22, a separator lens unit 23, a line sensor unit 24, the condenser lens unit 21, the mask member 22, And a module frame 25 to which the separator lens unit 23 and the line sensor unit 24 are attached. The condenser lens unit 21, the mask member 22, the separator lens unit 23, and the line sensor unit 24 are arranged in this order from the image sensor 10 side along the thickness direction of the image sensor 10.

  The condenser lens unit 21 is a unit in which a plurality of condenser lenses 21a, 21a,. As many condenser lenses 21a, 21a,... Are provided as there are passage holes 14c, 14c,. Each condenser lens 21 a is for condensing incident light, condenses the light that is transmitted through the image sensor 10 and is spreading, and guides it to a separator lens 23 a described later of the separator lens unit 23. Each condenser lens 21a has an incident surface 21b formed in a convex shape, and the vicinity of the incident surface 21b is formed in a cylindrical shape.

  By providing the condenser lens 21a, the incident angle to the separator lens 23a is increased (the incident angle is reduced), so that the aberration of the separator lens 23a can be suppressed and the object image interval on the line sensor 24a described later can be reduced. Can be small. As a result, the separator lens 23a and the line sensor 24a can be reduced in size. In addition, when the focus position of the subject image from the image pickup optical system is greatly deviated from the image pickup unit 1 (specifically, when it is greatly deviated from the image pickup device 10 of the image pickup unit 1), the contrast of the image is remarkably lowered. According to the embodiment, it is possible to suppress a decrease in contrast by the reduction effect of the condenser lens 21a and the separator lens 23a and to widen the focus detection range. Note that the condenser lens unit 21 may not be provided in the case of high-accuracy phase difference detection in the vicinity of the focal position, or when the dimensions of the separator lens 23a, the line sensor 24a, etc. are sufficient.

  The mask member 22 is disposed between the condenser lens unit 21 and the separator lens unit 23. In the mask member 22, two mask openings 22a and 22a are formed for each position corresponding to each separator lens 23a. That is, the mask member 22 divides the lens surface of the separator lens 23a into two regions, and only the two regions are exposed to the condenser lens 21a side. That is, the mask member 22 divides the light collected by the condenser lens 21a into two light fluxes and makes the light incident on the separator lens 23a. This mask member 22 can prevent harmful light from one separator lens 23a adjacent to the other separator lens 23a from entering. The mask member 22 need not be provided.

  The separator lens unit 23 includes a plurality of separator lenses 23a, 23a,..., And the separator lenses 23a, 23a,. The separator lenses 23a, 23a,... Are provided in the same number as the passage holes 14c, 14c,. Each separator lens 23a forms two light fluxes incident through the mask member 22 on the line sensor 24a as two identical subject images.

  The line sensor unit 24 includes a plurality of line sensors 24a, 24a,... And an installation portion 24b for installing the line sensors 24a, 24a,. The number of line sensors 24a, 24a,... Is the same as the number of passage holes 14c, 14c,. Each line sensor 24a receives an image formed on the imaging surface and converts it into an electrical signal. That is, the interval between two subject images can be detected from the output of the line sensor 24a, and the defocus amount (ie, defocus amount (Df amount)) of the subject image formed on the image sensor 10 based on the interval. It is possible to determine in which direction the focus is deviated (that is, the defocus direction) (hereinafter, the Df amount, the defocus direction, and the like are also referred to as defocus information).

  The condenser lens unit 21, the mask member 22, the separator lens unit 23, and the line sensor unit 24 configured as described above are disposed in the module frame 25.

  The module frame 25 is a member formed in a frame shape, and an attachment portion 25a that protrudes inward is provided on the inner periphery thereof. A first mounting portion 25b and a second mounting portion 25c are formed stepwise on the imaging element 10 side of the mounting portion 25a. Further, a third mounting portion 25d is formed on the side of the mounting portion 25a opposite to the image sensor 10.

  From the image sensor 10 side, the mask member 22 is attached to the second attachment portion 25c of the module frame 25, and the condenser lens unit 21 is attached to the first attachment portion 25b. The condenser lens unit 21 and the mask member 22 are formed so that the peripheral edge fits into the module frame 25 as shown in FIGS. 3 and 6 when attached to the first attachment portion 25b and the second attachment portion 25c, respectively. And thereby positioned with respect to the module frame 25.

  On the other hand, the separator lens unit 23 is attached to the third attachment portion 25 d of the module frame 25 from the opposite side of the image sensor 10. The third mounting portion 25d is provided with a positioning pin 25e and a direction reference pin 25f that protrude on the opposite side of the condenser lens unit 21. On the other hand, the separator lens unit 23 is formed with positioning holes 23b and direction reference holes 23c corresponding to the positioning pins 25e and the direction reference pins 25f, respectively. The diameters of the positioning pins 25e and the positioning holes 23b are set so as to be fitted. On the other hand, the diameters of the direction reference pin 25f and the direction reference hole 23c are set so as to fit gently. That is, the separator lens unit 23 inserts the positioning hole 23b and the direction reference hole 23c into the positioning pin 25e and the direction reference pin 25f of the third attachment part 25d, respectively, so that the direction when attaching to the third attachment part 25d, etc. The posture is defined, and the positioning is performed with respect to the third mounting portion 25d by fitting the positioning hole 23b and the positioning pin 25e. Thus, when the separator lens unit 23 is mounted with its orientation and position determined, the lens surfaces of the separator lenses 23a, 23a,... Face the condenser lens unit 21 and face the mask openings 22a, 22a. become.

  Thus, the condenser lens unit 21, the mask member 22, and the separator lens unit 23 are attached while being positioned with respect to the module frame 25. That is, the positional relationship between the condenser lens unit 21, the mask member 22, and the separator lens unit 23 is positioned via the module frame 25.

  The line sensor unit 24 is attached to the module frame 25 from the back side of the separator lens unit 23 (the side opposite to the condenser lens unit 21). At this time, the line sensor unit 24 is attached to the module frame 25 in a state where the light transmitted through each separator lens 23a is positioned so as to enter the line sensor 24a.

  Therefore, by attaching the condenser lens unit 21, the mask member 22, the separator lens unit 23, and the line sensor unit 24 to the module frame 25, light incident on the condenser lenses 21a, 21a,. Are transmitted through the mask member 22 and incident on the separator lenses 23a, 23a,..., And the light transmitted through the separator lenses 23a, 23a,... Forms an image on the line sensors 24a, 24a,. The lenses 21a, 21a,..., The mask member 22, the separator lenses 23a, 23a,... And the line sensors 24a, 24a,.

  The image sensor 10 and the phase difference detection unit 20 configured as described above are joined to each other. Specifically, the opening 31c of the package 31 in the image sensor 10 and the condenser lens 21a in the phase difference detection unit 20 are configured to fit each other. That is, the module frame 25 is bonded to the package 31 in a state where the condenser lenses 21a, 21a,... In the phase difference detection unit 20 are fitted into the openings 31c, 31c,. By doing so, the imaging device 10 and the phase difference detection unit 20 can be joined in a state of being positioned with respect to each other. In this way, the condenser lenses 21a, 21a,..., The separator lenses 23a, 23a,... And the line sensors 24a, 24a, etc. are integrated into a unit and attached to the package 31 in a united state.

  At this time, all the openings 31c, 31c,... And all the condenser lenses 21a, 21a,. Alternatively, only some of the openings 31c, 31c,... And the condenser lenses 21a, 21a,... Are fitted, and the remaining openings 31c, 31c,. You may comprise. In the latter case, the condenser lens 21a closest to the center of the imaging surface and the opening 31c are configured to be fitted to perform positioning within the imaging surface, and further, the condenser lens 21a and the aperture that are farthest from the center of the imaging surface. It is preferable that positioning is performed around the condenser lens 21a and the opening 31c (that is, the rotation angle) in the center of the imaging surface by being configured so as to be fitted with 31c.

  In this way, as a result of joining the image sensor 10 and the phase difference detection unit 20, a pair of mask openings of the condenser lens 21a and the mask member 22 are provided on the back side of the image sensor 10 for each of the passage holes 14c of the emission side mask 14b. 22a, 22a, separator lens 23a and line sensor 24a are arranged.

  In this way, by forming the openings 31c, 31c,... In the bottom plate 31a of the package 31 that accommodates the image sensor 10 with respect to the image sensor 10 configured to transmit light, the light transmitted through the image sensor 10 is formed. Can easily reach the back side of the package 31, and the phase difference detection unit 20 is disposed on the back side of the package 31 so that the light transmitted through the image sensor 10 is received by the phase difference detection unit 20. The configuration can be easily realized.

  In addition, the openings 31c, 31c,... Formed in the bottom plate 31a of the package 31 may adopt any configuration as long as the configuration allows the light transmitted through the image sensor 10 to pass through to the back side of the package 31. By forming the openings 31c, 31c,... Which are holes, the light transmitted through the image sensor 10 can reach the back side of the package 31 without being attenuated.

  Further, the phase difference detection unit 20 can be positioned with respect to the image sensor 10 by using the openings 31c, 31c,... By fitting the condenser lenses 21a, 21a,. . In the case where the condenser lenses 21a, 21a,... Are not provided, the phase difference detection unit for the image sensor 10 can be similarly formed by configuring the separator lenses 23a, 23a,. 20 positionings can be performed.

  At the same time, the bottom plate 31a of the package 31 can be passed through the condenser lenses 21a, 21a,... And close to the substrate 11a, so that the imaging unit 1 can be configured compactly.

  Further, three passage holes 14c are formed in the exit side mask 14b of the image sensor 10, and three sets of condenser lenses 21a, separator lenses 23a, and line sensors 24a are provided corresponding to the passage holes 14c, 14c, 14c. However, it is not limited to this. The number of these is not limited to three, and can be set to an arbitrary number. For example, as shown in FIG. 7, nine passing holes 14c, 14c,... May be formed, and nine sets of condenser lens 21a, separator lens 23a, and line sensor 24a may be provided.

  The operation of the imaging unit 1 configured as described above will be described below.

  When light from the subject enters the imaging unit 1, the light passes through the cover glass 33 and enters the glass substrate 19. The light passes through the glass substrate 19 and enters the back surface of the substrate 11 a of the image sensor 10. At this time, the light passes through the color filters 15r, 15g, and 15b, so that only light of a color corresponding to each color filter 15 enters the substrate 11a. The light incident on the substrate 11a passes through the substrate 11a and reaches the light receiving portions 11b, 11b,... On the surface of the substrate 11a. Since the incident side mask 14a is provided on the surface of the substrate 11a, light does not enter the vertical register 12 or the transfer path 13, and light enters only the light receiving portions 11b, 11b,. Each light receiving portion 11b absorbs light and generates electric charges. Here, not all of the light incident on the light receiving portion 11b is absorbed by the light receiving portion 11b, and a part of the light is transmitted through the light receiving portion 11b, but is emitted to a position where it has passed through the light receiving portion 11b. Since the side mask 14b is provided, the light transmitted through the light receiving portion 11b is reflected by the emission side mask 14b and enters the light receiving portion 11b again. The electric charge generated in the light receiving unit 11b is sent to the amplifier via the vertical register 12 and the transfer path 13, and is output as an electric signal. In this way, the image sensor 10 converts the subject image formed on the imaging surface into an electrical signal for creating an image signal by the light receiving units 11b converting the light into electrical signals on the entire imaging surface.

  However, the light transmitted through the light receiving portions 11b, 11b,... Of the image sensor 10 exits to the back side of the image sensor 10 through the passage holes 14c, 14c,. And the light which permeate | transmitted the image pick-up element 10 injects into the condenser lenses 21a, 21a, ... fitted to the openings 31c, 31c, ... of the package 31. The light condensed by passing through each condenser lens 21a is divided into two light beams when passing through each pair of mask openings 22a, 22a formed in the mask member 22, and enters each separator lens 23a. . The light thus divided into pupils passes through the separator lens 23a and forms an identical subject image at two positions on the line sensor 24a. The line sensor 24a creates and outputs an electrical signal from the subject image by photoelectric conversion.

  Next, processing in the body microcomputer 50 for the electrical signal converted by the image sensor 10 will be described.

  An electrical signal output from the image sensor 10 is input to the body microcomputer 50 via the image capturing unit controller 52. Then, the body microcomputer 50 obtains the subject image formed on the imaging surface by obtaining the position information of each light receiving unit 11b and the output data corresponding to the amount of light received by the light receiving unit 11b from the entire imaging surface of the image sensor 10. Get as an electrical signal.

  Here, even if the light receiving units 11b, 11b,... Receive the same amount of light, the accumulated charge amounts differ depending on the wavelength of the light, so that the outputs from the light receiving units 11b, 11b,. Correction is performed according to the type of the color filters 15r, 15g, and 15b provided. For example, an R pixel 11b provided with a red color filter 15r, a G pixel 11b provided with a green color filter 15g, and a B pixel 11b provided with a blue color filter 15b have colors corresponding to the respective color filters. When the same amount of light is received, the correction amount of each pixel is set so that the outputs from the R pixel 11b, the G pixel 11b, and the B pixel 11b are at the same level.

  In addition, in this embodiment, by providing the passage holes 14c, 14c,... Of the emission side mask 14b, the amount of received light in the portion corresponding to the passage holes 14c, 14c,. Less than As a result, the output data output from the pixels 11b, 11b,... Provided at the positions corresponding to the through holes 14c, 14c,. When image processing similar to that of data is performed, there is a possibility that images of portions corresponding to the passage holes 14c, 14c,... Are not properly captured (for example, they are captured darkly). Therefore, the output of each pixel 11b in the passage holes 14c, 14c,... Is corrected so as to eliminate the influence of the passage holes 14c, 14c,... (For example, the output of each pixel 11b in the passage holes 14c, 14c,. Etc.)

  Further, the reduction in output varies depending on the wavelength of light. Specifically, the longer the wavelength, the higher the transmittance of the substrate 11a, and the greater the decrease in output due to the passage hole 14c. Therefore, there is a difference in the decrease in output due to the passage hole 14c depending on the type of the color filters 15r, 15g, and 15b. Accordingly, the correction for eliminating the influence of the passage hole 14c on each pixel 11b corresponding to the passage hole 14c is made different in accordance with the wavelength of the light received by each pixel 11b. Specifically, for each pixel 11b corresponding to the passage hole 14c, the correction amount is increased as the wavelength of light received by each pixel 11b is longer.

  Here, in each pixel 11b, as described above, a correction amount for eliminating the difference in accumulated charge amount depending on the type of light received is set, and in addition to the correction for eliminating the difference in accumulated charge amount due to this color type. Thus, the correction for eliminating the influence of the passage hole 14c is made. That is, the correction amount for correcting the influence of the passage hole 14c is the correction amount for each pixel 11b corresponding to the passage hole 14c and the pixel 11b corresponding to a position other than the passage hole 14c and receiving the same color. This is the difference from the correction amount for the pixel 11b. In the present embodiment, the correction amount is varied for each color according to the relationship shown below. By doing so, a stable image output can be obtained.

Rk>Gk> Bk (1)
here,
Rk: R pixel correction amount of the passage hole 14c−R pixel correction amount other than the passage hole 14c Gk: G pixel correction amount of the passage hole 14c−G pixel correction amount other than the passage hole 14c Bk: B pixel correction amount of the passage hole 14c -It is set as B pixel correction amount other than the passage hole 14c.

  That is, among the three colors of red, green, and blue, red, which has a long wavelength, has the highest transmittance, so that the difference in correction amount at the red pixel is the largest. In addition, since blue, which has a short wavelength among the three colors, has the lowest transmittance, the difference in the correction amount between the blue pixels is the smallest.

  That is, the correction amount of the output of each pixel 11b of the image sensor 10 depends on whether or not each pixel 11b is located at a position corresponding to the passage hole 14c and the color type of the color filter 15 corresponding to each pixel 11b. To be determined. Each correction amount is set so that, for example, the white balance and / or luminance of the displayed image are equal by the output from the pixel 11b corresponding to the passage hole 14c and the output from the pixel 11b corresponding to a position other than the passage hole 14c. To be determined.

  The body microcomputer 50 corrects the output data from the light receiving portions 11b, 11b,... In this way, and then, based on the output data, the position information, color information, and luminance information in each light receiving portion, that is, the pixel 11b. Create an image signal containing. Thus, an image signal of the subject image formed on the imaging surface of the image sensor 10 is obtained.

  By correcting the output from the image sensor 10 in this way, the subject image can be appropriately captured even in the image sensor 10 provided with the passage holes 14c, 14c,.

  On the other hand, an electrical signal output from the line sensor unit 24 is also input to the body microcomputer 50. Based on the output from the line sensor unit 24, the body microcomputer 50 obtains the interval between the two subject images formed on the line sensor 24a, and uses the obtained interval to determine the subject image to be imaged on the image sensor 10. The focus state can be detected. For example, the two subject images formed on the line sensor 24a have a predetermined reference when the subject image formed on the image sensor 10 through the imaging lens is accurately formed (focused). Positioned at a predetermined reference position with a gap. On the other hand, when the subject image is formed in front of the image sensor 10 in the optical axis direction (front pin), the interval between the two subject images is narrower than the reference interval at the time of focusing. On the other hand, when the subject image is formed behind the image sensor 10 in the optical axis direction (rear pin), the interval between the two subject images is wider than the reference interval at the time of focusing. That is, after amplifying the output from the line sensor 24a, it is possible to know whether the in-focus state or the out-of-focus state, the front pin or the rear pin, or the amount of Df by calculating with the arithmetic circuit.

-Explanation of camera operation-
The operation of the camera 100 configured as described above will be described with reference to FIGS. FIG. 8 is a flowchart showing the operation of the camera 100 until the release button is fully pressed, and FIG. 9 is a flowchart showing the operation of the camera 100 after the release button is fully pressed.

  The following operations are mainly controlled by the body microcomputer 50.

  First, when the power switch 40a is turned on (step St1), communication between the camera body 4 and the interchangeable lens 7 is performed (step St2). Specifically, power is supplied to the body microcomputer 50 and various units in the camera body 4, and the body microcomputer 50 is activated. At the same time, electrodes are supplied to the lens microcomputer 80 and various units in the interchangeable lens 7 via the electrical sections 41a and 71a, and the lens microcomputer 80 is activated. The body microcomputer 50 and the lens microcomputer 80 are programmed to transmit and receive information to each other at the time of activation. For example, lens information relating to the interchangeable lens 7 is transmitted from the memory unit of the lens microcomputer 80 to the body microcomputer 50. 50 memory units.

  Subsequently, the body microcomputer 50 positions the focus lens group 72 at a predetermined reference position set in advance via the lens microcomputer 80 (step St3), and at the same time, opens the shutter unit 42 (see FIG. Step St4). Thereafter, the process proceeds to step St5 and waits until the photographer presses the release button 40b halfway.

  By doing so, the light that has passed through the interchangeable lens 7 and entered the camera body 4 passes through the shutter unit 42, further passes through the IR cut / OLPF 43, and enters the imaging unit 1. The subject image formed by the imaging unit 1 is displayed on the image display unit 44, and the photographer can observe an erect image of the subject via the image display unit 44. Specifically, the body microcomputer 50 reads an electrical signal from the image sensor 10 via the imaging unit control unit 52 at a constant cycle, performs predetermined image processing on the read electrical signal, and then creates an image signal. Then, the image display control unit 55 is controlled to display the live view image on the image display unit 44.

  Further, part of the light incident on the imaging unit 1 passes through the imaging element 10 and enters the phase difference detection unit 20.

  Here, when the release button 40b is half-pressed by the photographer (that is, the S1 switch (not shown) is turned on) (step St5), the body microcomputer 50 receives the signal from the line sensor 24a of the phase difference detection unit 20. After the output is amplified, it is calculated by an arithmetic circuit to detect whether it is in focus or not in focus (step St6). Furthermore, the body microcomputer 50 obtains the defocus information by obtaining the front pin or the rear pin and how much the defocus amount is (step St7). Thereafter, the process proceeds to step St10.

  Here, the phase difference detection unit 20 according to the present embodiment includes three sets of the condenser lens 21a, the mask openings 22a and 22a, the separator lens 23a, and the line sensor 24a, that is, measurement that performs focus detection by the phase difference detection method. There are three distance points. In the phase difference detection, the focus lens group 72 is driven based on the output of the set of line sensors 24a corresponding to the distance measuring points arbitrarily selected by the photographer.

  Alternatively, an automatic optimization algorithm is set in the body microcomputer 50 so that the focus lens group 72 is driven by selecting the distance measurement point closest to the camera and the subject from among the plurality of distance measurement points. Also good. In this case, it is possible to reduce the probability that a hollow photo or the like will occur.

  On the other hand, in parallel with steps St6 and St7, photometry is performed (step St8) and image blur detection is started (step St9).

  That is, in step St8, the amount of light incident on the image sensor 10 is measured by the image sensor 10. That is, in the present embodiment, since the above-described phase difference detection is performed using the light that has entered the image sensor 10 and has passed through the image sensor 10, the image sensor 10 is mounted in parallel with the phase difference detection. Can be used for photometry.

  Specifically, the body microcomputer 50 performs photometry by taking in an electrical signal from the image sensor 10 via the imaging unit controller 52 and measuring the intensity of the subject light based on the electrical signal. Then, the body microcomputer 50 determines the shutter speed and aperture value at the time of exposure according to the photographing mode from the photometric result according to a predetermined algorithm.

  Then, when the photometry is finished in step St8, image blur detection is started in step St9. Note that step St8 and step St9 may be performed in parallel.

  Thereafter, the process proceeds to step St10. In addition, after step St9, you may progress to step St12 instead of step St10.

  As described above, in the present embodiment, since the focus detection based on the above-described phase difference is performed using the light incident on the image sensor 10 and transmitted through the image sensor 10, in parallel with the focus detection, Photometry can be performed using the image sensor 10.

  In step St10, the body microcomputer 50 drives the focus lens group 72 based on the defocus information acquired in step St7.

  Then, the body microcomputer 50 determines whether or not a contrast peak has been detected (step St11). When the contrast peak is not detected (NO), the drive of the focus lens group 72 is repeated (step St10), while when the contrast peak is detected (YES), the drive of the focus lens group 72 is stopped and the focus lens group 72 is stopped. Is moved to a position where the contrast value reaches a peak, and then the process proceeds to step St11.

  Specifically, the focus lens group 72 is driven at a high speed to a position farther forward and backward than the position predicted as the in-focus position based on the defocus amount calculated in step St7. Thereafter, the contrast peak is detected while the focus lens group 72 is driven at a low speed toward the predicted position as the in-focus position.

  When the release button 40b is pressed halfway by the photographer, various information related to photographing is displayed together with the photographed image on the image display unit 44, and the photographer confirms various information via the image display unit 44. be able to.

  In step St12, the process waits until the photographer fully presses the release button 40b (that is, the S2 switch (not shown) is turned on). When the release button 40b is fully pressed by the photographer, the body microcomputer 50 temporarily closes the shutter unit 42 (step St13). Thus, while the shutter unit 42 is in the closed state, the charges accumulated in the light receiving portions 11b, 11b,...

  Thereafter, the body microcomputer 50 starts correction of image blur based on communication information between the camera body 4 and the interchangeable lens 7 or arbitrary designation information of the photographer (step St14). Specifically, the blur correction lens driving unit 74 a in the interchangeable lens 7 is driven based on information from the blur detection unit 56 in the camera body 4. Further, according to the photographer's intention, (i) the blur detection unit 84 and the blur correction lens driving unit 74a in the interchangeable lens 7 are used, and (ii) the blur detection unit 56 and the blur correction unit 45 in the camera body 4 are provided. Either (iii) using the blur detection unit 84 in the interchangeable lens 7 or the blur correction unit 45 in the camera body 4 can be selected.

  The driving of the image blur correction unit is started when the release button 40b is half-pressed, so that the movement of the subject to be focused is reduced and AF can be performed more accurately.

  In parallel with the start of image blur correction, the body microcomputer 50 narrows down the diaphragm 73 via the lens microcomputer 80 so that the diaphragm value obtained from the photometric result in step St8 is obtained (step St15).

  In this way, the correction of image blur is started, and when the narrowing is completed, the body microcomputer 50 opens the shutter unit 42 based on the shutter speed obtained from the photometric result in step St8 (step St16). Thus, by opening the shutter unit 42, the light from the subject enters the image sensor 10, and the image sensor 10 accumulates charges for a predetermined time (step St17).

  Then, the body microcomputer 50 closes the shutter unit 42 based on the shutter speed, and ends the exposure (step St18). After the exposure is completed, the body microcomputer 50 reads the image data from the imaging unit 1 via the imaging unit control unit 52, and after the predetermined image processing, the image data is sent to the image display control unit 55 via the image reading / recording unit 53. Output. As a result, the captured image is displayed on the image display unit 44. The body microcomputer 50 stores image data in the image storage unit 58 via the image recording control unit 54 as necessary.

  Thereafter, the body microcomputer 50 ends the image blur correction (step St19) and opens the diaphragm 73 (step St20). Then, the body microcomputer 50 opens the shutter unit 42 (step St21).

  When the reset is completed, the lens microcomputer 80 notifies the body microcomputer 50 of the completion of the reset. The body microcomputer 50 waits for the reset completion information from the lens microcomputer 80 and the completion of the series of processes after exposure, and then confirms that the state of the release button 40b is not depressed, and ends the photographing sequence. Thereafter, the process returns to step St5 and waits until the release button 40b is half-pressed.

  When the power switch 40a is turned off (step St22), the body microcomputer 50 moves the focus lens group 72 to a predetermined reference position set in advance (step St23) and closes the shutter unit 42. (Step St24). Then, the operation of the body microcomputer 50 and various units in the camera body 4 and the lens microcomputer 80 and various units in the interchangeable lens 7 are stopped.

  Thus, in the AF operation of this embodiment, first, the defocus information is acquired by the phase difference detection unit 20, and the focus lens group 72 is driven based on the defocus information. Then, the position of the focus lens group 72 where the contrast value calculated based on the output from the image sensor 10 reaches a peak is detected, and the focus lens group 72 is positioned at this position. In this way, since defocus information can be detected before the focus lens group 72 is driven, there is no need to drive the focus lens group 72 for the time being as in the conventional contrast detection method AF. The autofocus processing time can be shortened. In addition, since the focus is finally adjusted by the contrast detection method AF, it is possible to directly capture the contrast peak, and unlike the phase difference detection method AF, there are various methods such as open back correction (focus shift due to the aperture opening degree). Since no correction calculation is required, a highly accurate focus performance can be obtained. In particular, it is possible to focus on a subject with a repetitive pattern or a subject with extremely low contrast with higher accuracy than the conventional phase difference detection method AF.

  Since the AF operation of the present embodiment includes phase difference detection, the defocus information is acquired by the phase difference detection unit 20 using light transmitted through the image sensor 10. Metering and acquisition of defocus information by the phase difference detection unit 20 can be performed in parallel. That is, since the phase difference detection unit 20 receives the light transmitted through the image sensor 10 and acquires defocus information, the image sensor 10 is always irradiated with light from the subject when acquiring the defocus information. . Therefore, photometry is performed using light transmitted through the image sensor 10 during autofocus. By doing so, it is not necessary to separately provide a photometric sensor, and since photometry can be performed before the release button 40b is fully pressed, exposure is completed after the release button 40b is fully pressed. Time (hereinafter also referred to as a release time lag) can be shortened.

  Further, even if the photometry is performed before the release button 40b is fully pressed, it is possible to prevent the processing time after the release button 40b is half-pressed by performing photometry in parallel with the autofocus. At this time, there is no need to provide a mirror for guiding light from the subject to the photometric sensor or the phase difference detection unit.

  Conventionally, part of the light guided from the subject to the imaging device is guided to the phase difference detection unit provided outside the imaging device by a mirror or the like, whereas the light guided to the imaging unit 1 is used as it is. Since the focus state can be detected by the phase difference detection unit 20, the defocus information can be acquired with high accuracy.

  In the above-described embodiment, the so-called hybrid AF, in which the contrast AF is performed after the phase difference is detected, is adopted, but the present invention is not limited to this. For example, phase difference detection AF that performs AF based on defocus information acquired by phase difference detection may be used. Also, the hybrid AF, the phase difference detection AF, and the contrast detection AF that performs focusing based on only the contrast value without performing the phase difference detection may be switched.

-Effect of Embodiment 1-
Therefore, according to the first embodiment, the phase difference detection unit 20 configured to allow light to pass through the image sensor 10 and receive the light that has passed through the image sensor 10 and perform focus detection by the phase difference detection method is provided. And the body control unit 5 controls the image sensor 10 and performs focus adjustment by driving and controlling the focus lens group 72 based on at least the detection result of the phase difference detection unit 20, thereby using the image sensor 10. The various processes and the autofocus using the phase difference detection unit 20 can be performed in parallel, and the processing time can be shortened.

  Even if various processes using the image sensor 10 and autofocus using the phase difference detection unit 20 are not performed in parallel, according to the above configuration, when light is incident on the image sensor 10, the phase difference Since light is also incident on the detection unit 20, various processes using the image sensor 10 and autofocus using the phase difference detection unit 20 can be easily switched by switching the control of the body control unit 5. . That is, since it is not necessary to move the movable mirror forward and backward as compared with the conventional configuration in which the moving direction of the light from the subject is switched between the image pickup element and the phase difference detection unit by moving the movable mirror forward and backward, the image pickup element 10 is Since various processes used and auto-focus using the phase difference detection unit 20 can be switched immediately, and no sound is generated as the movable mirror advances and retreats, various processes and levels using the image sensor 10 can be avoided. The auto focus using the phase difference detection unit 20 can be switched silently.

  Thus, the convenience of the camera 100 can be improved.

  Specifically, the image sensor 10 is configured to allow light to pass through, and by providing the phase difference detection unit 20 that receives the light that has passed through the image sensor 10 and performs focus detection by a phase difference detection method, Like the phase difference detection AF, AF using the phase difference detection unit 20 and photometry using the image sensor 10 can be performed in parallel. By doing so, it is not necessary to perform photometry after the release button 40b is fully pressed, and the release time lag can be shortened. Further, even if the photometry is performed before the release button 40b is fully pressed, it is possible to prevent the processing time after the release button 40b is half-pressed by performing photometry in parallel with the autofocus. Furthermore, since photometry is performed using the image sensor 10, there is no need to separately provide a photometric sensor. Furthermore, there is no need to provide a movable mirror for guiding light from the subject to a photometric sensor or a phase difference detection unit. Therefore, power consumption can be suppressed.

  Further, even in the hybrid AF described above, switching from phase difference detection by the phase difference detection unit 20 to contrast detection using the image sensor 10 is performed without performing switching of an optical path using a conventional movable mirror or the like. Since it can be performed immediately by the control in the body controller 5, the time required for the hybrid AF can be shortened. Further, since the movable mirror is unnecessary, noise due to the movable mirror is eliminated and the hybrid AF can be performed silently.

  Furthermore, in the conventional configuration in which light traveling from the subject toward the image sensor 10 is directed to a phase difference detection unit disposed at a location different from the back side of the image sensor 10 using a movable mirror or the like, The focus adjustment accuracy is not high due to the difference between the optical path and the optical path at the time of phase difference detection, the installation error of the movable mirror, etc. In this embodiment, the phase difference detection unit 20 receives light passing through the image sensor 10. Since the phase difference detection method focus detection is performed, the phase difference detection method focus detection can be performed while maintaining the same optical path as that at the time of exposure, and there is no member that causes an error such as a movable mirror. Acquisition of the defocus amount based on detection can be performed with high accuracy.

  As described above, even when the image sensor 10 is configured to transmit light, the image sensor 10 can be reinforced by bonding the glass substrate 19 to the image sensor 10. That is, if the image sensor 10 is configured to transmit light, the image sensor 10 becomes very thin and the strength is reduced. Therefore, the image pickup device 10 can be reinforced by bonding the glass substrate 19 to the image pickup device 10. In the present embodiment, the glass substrate 19 is bonded to the back surface of the substrate 11a with respect to the back-illuminated imaging element 10, but the glass substrate 19 is optically transparent and transmits light. The glass substrate 19 can be prevented from obstructing the incidence of light on the image sensor 10. That is, by using the glass substrate 19, it is possible to reinforce the image sensor 10 without affecting the incidence or emission of light to the image sensor 10.

-Modification 1-
Below, the modification of this embodiment is demonstrated. FIG. 10 is a cross-sectional view of the imaging unit 210 according to the first modification.

  In the imaging unit 1, the imaging unit 1 is configured by joining the imaging element 10 and the phase difference detection unit 20 via the package 31. However, the imaging unit 201 according to the first modification includes these as semiconductors. Manufactured in process. The imaging unit 201 is the same as the imaging unit 1 with respect to the basic configuration of the imaging element 10 and the glass substrate 19. However, the protective layer 18 is not provided on the surface of the substrate 11a of the imaging device 10, and instead, the first low refractive index layer 225, the condenser lens layer 221, and the second in order from the surface of the substrate 11a. A low refractive index layer 226, a third low refractive index layer 227, a separator lens layer 223, a fourth low refractive index layer 228, and a protective layer 229 are laminated.

  The first, second, third, and fourth low refractive index layers 225, 226, 227, and 228 are made of a transparent material having a relatively low refractive index. On the other hand, the condenser lens layer 221 and the separator lens layer 223 are made of a transparent material having a relatively high refractive index. The first, second, third, and fourth low refractive index layers 225, 226, 227, and 228 may be made of the same material or different materials. Similarly, the condenser lens layer 221 and the separator lens layer 223 may be made of the same material or different materials.

  In the first low-refractive index layer 225, the bonding surface with the condenser lens layer 221 has a portion corresponding to the passage hole 14c of the emission side mask 14b provided on the substrate 11a, which is recessed toward the substrate 11a. Correspondingly, the portion of the condenser lens layer 221 that is bonded to the first low-refractive index layer 225 has a portion corresponding to the through hole 14c bulges toward the substrate 11a. That is, of the joint surface between the first low refractive index layer 225 and the condenser lens layer 221, the portion corresponding to the passage hole 14c forms a lens surface, and the condenser lens layer 221 functions as a condenser lens.

  A mask member 222 is provided on the bonding surface between the second low refractive index layer 226 and the third low refractive index layer 227. In the mask member 222, two mask openings 222a and 222a are formed at positions corresponding to the passage holes 14c.

  Further, the surface of the third low refractive index layer 227 that is bonded to the separator lens layer 223 has a concave portion on the substrate 11a side corresponding to the passage hole 14c. Specifically, the concave portion has a shape in which two concave curved surfaces are adjacent to each other. On the other hand, the joint surface of the separator lens layer 223 with the third low-refractive index layer 227 corresponds to the third low-refractive index layer 227, and a portion corresponding to the passage hole 14c is convex toward the substrate 11a. Bulges. Specifically, the convex portion has a shape in which two convex curved surfaces are adjacent to each other. That is, in the joint surface between the third low refractive index layer 227 and the separator lens layer 223, the portion corresponding to the passage hole 14c forms two lens surfaces, and the separator lens layer 223 functions as a separator lens.

  Furthermore, a line sensor 224 is provided on the joint surface between the fourth low refractive index layer 228 and the protective layer 229 at a position corresponding to the passage hole 14c.

  The first low refractive index layer 225, the condenser lens layer 221, the second low refractive index layer 226, the third low refractive index layer 227, the separator lens layer 223, the fourth low refractive index layer 228, and the protective layer 229 provide a phase difference. A detection unit 220 is configured. As described above, the glass substrate 19, the image sensor 10, and the phase difference detection unit 220 may be manufactured by a semiconductor process.

-Modification 2-
Next, an image sensor 310 according to Modification 2 will be described with reference to FIG. FIG. 11 is a cross-sectional view of the image sensor 310.

  Unlike the image sensor 10 that is a CCD image sensor, the image sensor 310 is a CMOS image sensor. Specifically, the imaging element 310 includes a photoelectric conversion unit 311 made of a semiconductor material, a transistor 312, a signal line 313, a mask 314, and a color filter 315.

  The photoelectric conversion unit 311 includes a substrate 311a and light receiving units 311b, 311b,. A transistor 312 is provided for each light receiving unit 311b. The charge accumulated in the light receiving portion 311b is amplified by the transistor 312 and output to the outside through the signal line 313.

  Like the mask 14, the mask 314 includes an incident side mask 314a and an emission side mask 314b. The incident side mask 314 a is provided adjacent to the light receiving portion 311 b and prevents light from entering the transistor 312 and the signal line 313. Further, the emission side mask 314b is provided with a plurality of passage holes 314c for emitting the light transmitted through the light receiving portion 311b to the back side of the image sensor 310.

  The color filter 315 has the same configuration as the color filter 15.

  In the CMOS image sensor, since the amplification factor of the transistor 312 can be set for each light receiving portion 311b, whether or not each light receiving portion 311b is positioned at a position corresponding to the passage hole 314c. Or setting based on the color type of the color filter 315 corresponding to each light receiving portion 311b, thereby preventing the image of the portion corresponding to the through holes 314c, 314c,. Can do.

-Modification 3-
Next, an imaging unit 401 according to Modification 3 will be described with reference to FIGS. FIG. 12 is a cross-sectional view of the image sensor 410 of the image pickup unit 401, and FIG. 13 is a cross-sectional view showing a state in which the image sensor 410 is attached to the circuit board 432.

  The imaging unit 401 differs from the imaging unit 1 in that light from a subject is incident on the front surface, not the back surface of the substrate of the image sensor. Therefore, the same components as those of the imaging unit 1 are denoted by the same reference numerals, description thereof is omitted, and different components are mainly described.

  The imaging unit 401 includes an imaging element 410 for converting a subject image into an electrical signal, a glass substrate 19 bonded to the imaging element 410, a package for holding the imaging element 410, and phase difference detection type focus detection. A phase difference detection unit for performing the above. The package and the phase difference detection unit have the same configuration as that of the imaging unit 1 although not shown.

  The imaging element 410 is a back-illuminated interline CCD image sensor, and as shown in FIG. 12, a photoelectric conversion unit 11 made of a semiconductor material, a vertical register 12, a transfer path 13, and a mask 414. And a color filter 15 and a microlens 416.

  On the surface of the substrate 11a, light receiving portions 11b, 11b,... Are provided in minute square pixel regions arranged in a matrix. A vertical register 12 is provided on the surface of the substrate 11a adjacent to each light receiving portion 11b. Further, a transfer path 13 is provided so as to overlap the vertical register 12. A mask 414 is provided so as to cover the vertical register 12 and the transfer path 13.

  Unlike the mask 14 according to the imaging unit 1, the mask 414 is provided only on the incident side of light from the subject. Specifically, the mask 414 is provided so as to cover the vertical register 12 and the transfer path 13 from the side opposite to the substrate 11a. Thus, the mask 414 prevents light from the subject side from entering the vertical register 12 and the transfer path 13.

  Further, a protective layer 18 made of an optically transparent resin is provided on the surface of the substrate 11a so as to cover the light receiving portion 11b, the vertical register 12, the transfer path 13, and the mask 414.

  The color filter 15 is laminated on the surface of the protective layer 18 (that is, the surface of the protective layer 18 opposite to the substrate 11a). The color filter 15 is a color filter containing a dye system or a pigment system pigment.

  The microlens 416 is made of an optically transparent resin, collects light and makes it incident on the light receiving unit 11 b, and is stacked on the color filter 15. Specifically, the microlens 416 is a convex lens that is provided for each light receiving unit 11b, that is, for each color filter 15, and bulges in a convex shape on the subject side (that is, the side opposite to the substrate 11a). The microlens 416 can efficiently irradiate the light receiving portion 11b.

  Further, a protective layer 17 made of an optically transparent resin is laminated on the surface (convex surface) of the microlens 416.

  The glass substrate 19 is bonded to the back surface of the substrate 11a by anodic bonding.

  In the imaging device 10 configured as described above, the light collected by the microlenses 416, 416,... Enters the color filters 15r, 15g, and 15b, and only the light of the color corresponding to each color filter 15 is obtained. The light passes through the color filter 15 and reaches the surface of the substrate 11a. In the substrate 11a, only the light receiving portions 11b, 11b,... Are exposed, and the vertical register 12, the transfer path 13, and the like are covered with the mask 414. Therefore, the light reaching the substrate 11a is directed to the light receiving portions 11b, 11b,. Only incident. Each light receiving portion 11b absorbs light and generates electric charges. The electric charge generated in each light receiving unit 11b is sent to the amplifier via the vertical register 12 and the transfer path 13 and is output as an electric signal. At this time, since light of a specific color transmitted through the color filters 15r, 15g, and 15b is incident on the light receiving portions 11b, 11b,..., The colors corresponding to the color filters 15 are received from the light receiving portions 11b. The received light quantity is obtained as an output. Thus, the image sensor 410 converts the subject image formed on the imaging surface into an electrical signal by performing photoelectric conversion at the light receiving portions 11b, 11b,... On the entire imaging surface.

  On the other hand, a part of the light incident on the light receiving part 11b is not absorbed by the light receiving part 11b but passes through the light receiving part 11b. Since the substrate 11a is very thin (that is, the substrate 11a is formed to have a thickness that allows light to pass through), the light transmitted through the light receiving portion 11b passes through the substrate 11a, and further, the glass substrate 19 Is transmitted to the back side of the image sensor 410.

  Similar to the imaging unit 1, a phase difference detection unit is provided on the back side of the imaging element 410, and the phase difference detection unit uses the light transmitted through the imaging element 410 to detect the focus of the phase difference detection method. I do.

  The imaging element 410 configured as described above is mounted on the circuit board 432 of the package.

  Specifically, the light receiving portion 11b, the vertical register 12, the transfer path 13, the mask 414, the color filter 15, the microlens 416, the protective layers 17 and 18 and the like are not provided on the peripheral portion of the substrate 11a of the image sensor 410. The wiring for enabling electrical connection with the transfer path 13 and the vertical register 12 is exposed. On the other hand, a circuit pattern is provided on the back surface (the surface opposite to the subject) of the circuit board 432 at a position facing the wiring of the substrate 11 a of the image sensor 410. Then, as shown in FIG. 13, the peripheral portion of the substrate 11a of the image sensor 410 is overlapped with the circuit board 432 from the opposite side to the subject, and the two are joined by thermal welding to connect the wiring of the substrate 11a of the image sensor 410. The circuit pattern of the circuit board 432 is electrically connected.

  Therefore, even when the image sensor 410 is configured to transmit light, the image sensor 410 can be reinforced by bonding the glass substrate 19 to the image sensor 410. That is, if the image sensor 410 is configured to transmit light, the image sensor 410 becomes very thin and the strength is reduced. Therefore, the image pickup element 410 can be reinforced by bonding the glass substrate 19 to the image pickup element 410. And in the structure which makes light inject from the surface of the board | substrate 11a instead of back surface irradiation, although the glass substrate 19 is joined to the back surface of the board | substrate 11a, this glass substrate 19 is optically transparent and permeate | transmits light. Therefore, it is possible to prevent the glass substrate 19 from interfering with the emission of light from the image sensor 410. That is, by using the glass substrate 19, it is possible to reinforce the image sensor 410 without affecting the emission of light from the image sensor 410.

  In addition, the same effects as the imaging unit 1 can be achieved.

<< Embodiment 2 of the Invention >>
Next, an imaging unit 501 according to Embodiment 2 of the present invention will be described with reference to FIG. FIG. 14 is a cross-sectional view of the image sensor 510 of the imaging unit 501.

  An imaging unit 501 according to the second embodiment is different from the first embodiment in that it does not include a phase difference detection unit. Therefore, configurations similar to those of the first embodiment are denoted by the same reference numerals, description thereof is omitted, and different configurations are mainly described.

  The imaging unit 501 includes an imaging element 510 for converting a subject image into an electrical signal, and a glass substrate 19 bonded to the imaging element 510.

  The configuration of the image sensor 510 is the same as that of the first embodiment except for the configuration of the emission side mask 514b. That is, the mask 514 includes an incident side mask 514a provided on the surface of the substrate 11a, and an emission side mask 514b provided so as to cover the light receiving unit 11b, the vertical register 12, and the transfer path 13 from the side opposite to the substrate 11a. have. The emission side mask 514b is not provided with a passage hole, and completely covers the light receiving unit 11b, the vertical register 12, and the transfer path 13 from the side opposite to the substrate 11a.

  In the imaging device 510 configured as described above, all the light transmitted through the light receiving portions 11b, 11b,... Is reflected by the emission side mask 514b, and is incident again on the light receiving portions 11b, 11b,. Are not emitted to the back side of the image sensor 510.

  That is, the image sensor 510 according to the second embodiment is a back-illuminated image sensor and does not perform phase difference detection. As described above, regardless of whether or not the phase difference detection type focus detection is performed, as long as the imaging device is a back-illuminated type, it is necessary to allow the light to pass through the substrate 11a. In the configuration in which light is transmitted through the substrate 11a, it is necessary to form the substrate 11a thin enough to transmit light. As described above, by bonding the glass substrate 19 to the image sensor 510, the image sensor 510 is provided. The image pickup element 510 can be reinforced without affecting the incidence of light.

<< Other Embodiments >>
The present invention may be configured as follows with respect to the above embodiment.

  For example, the configuration of the image sensor is not limited to the above configuration, and any configuration can be adopted as long as light is transmitted through the image sensor. Further, the phase difference detection unit is not limited to the above configuration.

  Moreover, joining of an image pick-up element and an optical transparent substrate may be implement | achieved by forming an image pick-up element on an optical transparent substrate, for example.

  Moreover, although the said embodiment demonstrated the structure which mounted the imaging unit 1 in the camera, it is not restricted to this. For example, the imaging unit 1 can be mounted on a video camera.

  In addition, the configuration is described in which AF is started when the photographer presses the release button 40b halfway (that is, when the S1 switch is turned on). However, even if the release button 40b is subjected to AF before halfway pressing. Good. Further, although the configuration has been described in which AF is terminated when it is determined that the focus is achieved, AF may be continued after the focus determination, or AF may be performed continuously without performing the focus determination.

  In the above-described embodiment, the substrate 11a may be completely removed by polishing, etching, or the like. In that case, the glass substrate 19 may be directly joined to the light receiving part 11b. In addition, the light receiving portion 11 b may be directly formed on the glass substrate 19.

  In addition, the above embodiment is an essentially preferable illustration, Comprising: It does not intend restrict | limiting the range of this invention, its application thing, or its use.

  As described above, the present invention is useful for an imaging unit including an imaging device that performs photoelectric conversion.

1, 201, 401, 501 Imaging unit 10, 310, 410 Imaging element 11a Substrate (semiconductor substrate)
11b Light receiver 15 Color filter (interference filter)
20,220 Phase difference detection unit (phase difference detection unit)
21a condenser lens 221 condenser lens layer (condenser lens)
23a Separator lens 223 Separator lens layer (Separator lens)
24a, 224 line sensor 31 package

Claims (19)

An imaging device having a semiconductor substrate and a light receiving portion provided on the semiconductor substrate, configured to convert light received by the light receiving portion into an electrical signal by photoelectric conversion, and to transmit light;
An imaging unit comprising: an optically transparent substrate that is bonded to the imaging element and transmits light. The imaging unit according to claim 1,
An imaging unit further comprising a phase difference detection unit that receives light that has passed through the imaging element and performs focus detection by a phase difference detection method. The imaging unit according to claim 2,
The said phase difference detection part is an imaging unit provided in the opposite side to the said optically transparent substrate with respect to the said image pick-up element. The imaging unit according to claim 3,
The phase difference detection unit includes: a separator lens that divides the light transmitted through the imaging device into a pupil; and a sensor that detects the light divided into the separator lens. The imaging unit according to claim 4,
The phase difference detection unit further includes a condenser lens that is provided closer to the imaging element than the separator lens and collects light transmitted through the plurality of light receiving units of the imaging element and causes the light to enter the separator lens. unit. The imaging unit according to claim 2,
The said phase difference detection part is an imaging unit provided in the opposite side to the said image pick-up element with respect to the said optical transparent substrate. The imaging unit according to claim 6,
The phase difference detection unit includes: a separator lens that divides the light transmitted through the imaging device into a pupil; and a sensor that detects the light divided into the separator lens. The imaging unit according to claim 7,
The imaging unit further comprising a condenser lens that is provided closer to the imaging element than the separator lens and collects light transmitted through the imaging element and causes the light to enter the separator lens. The imaging unit according to claim 4 or 5,
The phase difference detection unit is an imaging unit formed on the semiconductor substrate by a semiconductor process. The imaging unit according to any one of claims 2 to 8,
Further comprising a package in which the phase difference detection unit is disposed,
The imaging element is an imaging unit attached to the package. The imaging unit according to any one of claims 4, 5, 7, and 8,
The sensor is an imaging unit which is a line sensor. The imaging unit according to any one of claims 1 to 11,
The image pickup unit and the optically transparent substrate are image pickup units in which anodic bonding is performed. The imaging unit according to claim 12,
The semiconductor substrate of the imaging device is a Si single crystal,
The imaging unit, wherein the optically transparent substrate is a borosilicate glass substrate. The imaging unit according to any one of claims 1 to 13,
The thickness of the said semiconductor substrate of the said image pick-up element is an imaging unit which is 5 micrometers or less. The imaging unit according to any one of claims 1 to 14,
An imaging unit in which an electrical connection terminal is provided on a peripheral portion of the semiconductor substrate. The imaging unit according to any one of claims 1 to 3,
The image sensor is configured to receive light transmitted through the optical transparent substrate,
An imaging unit in which an interference filter is provided on a surface of the optically transparent substrate facing the imaging element. The imaging unit according to claim 16,
The interference unit is an imaging unit that is a Bayer array filter that transmits the three primary colors of RGB according to an interference phenomenon. An image sensor having a light receiving portion, configured to convert light received by the light receiving portion into an electrical signal by photoelectric conversion, and to transmit light;
An imaging unit comprising: an optically transparent substrate that is bonded to the imaging element and transmits light. The imaging unit according to claim 18,
An imaging unit further comprising a phase difference detection unit that receives light that has passed through the imaging element and performs focus detection by a phase difference detection method.

Images